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  • 101.
    Alipour, Yousef
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Viklund, Peter
    Henderson, Pamela
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    The analysis of furnace wall deposits in a low-NOx waste wood-fired bubbling fluidised bed boiler2012Inngår i: VGB PowerTech Journal, ISSN 1435-3199, Vol. 92, nr 12, s. 96-100Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    Increasing use is being made of biomass as fuel for electricity production as the price of natural wood continues to rise. Therefore, more use is being made of waste wood (recycled wood). However, waste wood contains more chlorine, zinc and lead, which are believed to increase corrosion rates. Corrosion problems have occurred on the furnace walls of a fluidised bed boiler firing 100 % waste wood under low-NOx conditions. The deposits have been collected and analysed in order to understand the impact of the fuel.

    Fulltekst (pdf)
    fulltext
  • 102. Alirezaei, Mohammadamin
    et al.
    Doostmohammadi, Hamid
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Microstructure evolution in cast and equilibrium heat-treated CuZn30-(Si) alloys2016Inngår i: International Journal of Cast Metals Research, ISSN 1364-0461, E-ISSN 1743-1336, Vol. 29, nr 4, s. 222-227Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The main object of this work was to investigate the effect of Si addition and heat treatment on the microstructure of CuZn30 alloy. The alloys were prepared by casting and then the chemical composition, microstructure and phases were determined by optical and scanning electron microscope and XRD analysis. The resulting microstructures contained two phases, alpha and beta', with volume fraction depending on silicon content. Increments of Si content led to the formation of a Widmanstatten structure. It was also found that the silicon dissolved completely in alpha + beta phases and the lattice parameters of both alpha- and beta'-phases increased as the Si content increased. Hardness tests showed that hardness of both the as-cast and heat-treated samples increased as the Si content increased, and a significant increment of hardness in heat-treated alloy was due to the formation of a martensite phase.

  • 103. Allen, S. L.
    et al.
    Wampler, W. R.
    McLean, A. G.
    Whyte, D. G.
    West, W. P.
    Stangeby, P. C.
    Brooks, N. H.
    Rudakov, D. L.
    Phillips, V.
    Rubel, Marek J.
    KTH, Skolan för elektro- och systemteknik (EES), Fusionsplasmafysik. KTH, Skolan för elektro- och systemteknik (EES), Centra, Alfvénlaboratoriet.
    Matthews, G. F.
    Nagy, A.
    Ellis, R.
    Bozek, A. S.
    C-13 transport studies in L-mode divertor plasmas on DIII-D2005Inngår i: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 337-39, nr 03-jan, s. 30-34Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    (CH4)-C-13 was injected with a toroidally-symmetric gas system into 22 identical lower-single-null L-mode discharges on DIII-D. The injection level was adjusted so that it did not significantly perturb the core or divertor plasmas, with a duration of similar to 3 s on each shot, for a total of similar to 300 T L of injected particles. The plasma shape remained very constant; the divertor strike points were controlled to similar to 1 cm at the divertor plate. At the beginning of the subsequent machine vent, 29 carbon tiles were removed for nuclear reaction analysis of C-13 content to determine regions of carbon deposition. It was found that only the tiles inboard of the inner strike point had appreciable 1 3 C above background. Visible spectroscopy measurements of the carbon injection and comparisons with modeling are consistent with carbon transport by means of scrape-off layer flow.

  • 104.
    Allertz, Carl
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Mikro-modellering.
    Sulfur and nitrogen in ladle slag2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The present work deals with some aspects of slags related to secondary metallurgy in the steelmaking process. More specifically the focus is given to sulfur and nitrogen in ladle slags. Even though slags have been fairly well-researched in the past, the available data for these elements in typical ladle slag compositions is rather scarce. In some cases the available data is in discordance. There are also inconsistencies between the literature data and what is commonly observed in the industrial processes.

    Sulfide capacities were measured at steelmaking temperatures, 1823–1873 K, in ladle slags. The data was found to be in reasonable agreement with the industrial process norms. The sulfide capacity was found to increase with the basic oxides CaO and MgO; and decrease with the acidic components Al2O3 and SiO2. The sulfide capacity was also found to increase with temperature.

    The dependence of sulfide capacity on the oxygen partial pressure, for slags containing multivalent elements, was investigated experimentally at 1873 K with a slag containing vanadium oxide. A strong dependence of oxygen partial pressure was observed. The sulfide capacity increase by more than two orders of magnitude when the oxygen partial pressure was increased from 4.6×10-16 atm to 9.7×10-10 atm.

    The nitrogen solubility and the effect of carbon was investigated in typical ladle slags and the CaO–MgO–SiO2 system at 1873 K. Carbon increases the nitrogen solubility substantially. In the absence of carbon, the nitrogen solubility is extremely low. Low concentrations of cyanide was detected in the carbon saturated slag. This was much lower than the total nitrogen content and formation of cyanide cannot explain the large increase.

    The possibility of removing sulfur with oxidation from used ladle slag was investigated experimentally at 1373–1673 K. The sulfur removal of mostly solid slag was found to be a slow process, and would not suitable for industrial practice. At 1673 K the slag was mostly liquid and more than 85% of the sulfur was removed after 60 min of oxidation in pure oxygen atmosphere.

     

    Fulltekst (pdf)
    Thesis
  • 105.
    Allertz, Carl
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Mikro-modellering.
    Du, Sichen
    Possibility of Sulfur Removal from Ladle Slag by Oxidation in the Temperature Range 1373-1673 K2015Inngår i: Journal of Sustainable Metallurgy, ISSN 2199-3823, Vol. 1, nr 3, s. 229-239Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Experiments were conducted to investigate the possibility of removing sulfur from used ladle slag by oxidation. Slag samples (solid, two-phase mixture, and liquid with a small fraction of solid MgO particles) were subjected to an oxygen-rich atmosphere in the temperature range 1373–1673 K. The sulfur removal from the samples of solid and two-phase mixture was found to be a slow process due to the slow diffusion. The sulfur removal was found to have little dependence on temperature in the range 1373–1573 K. When the slag was mostly liquid (at 1673 K), the sulfur removal was significantly increased. More than 85 % of the sulfur could be removed after 60 min of oxidation in pure oxygen. An increase in oxygen partial pressure was found to increase the desulfurization slightly. Increasing the Al2O3 content in the slag decreased the degree of sulfur removal.

  • 106.
    Allertz, Carl
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Mikro-modellering.
    Du, Sichen
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Mikro-modellering.
    The Effect of Oxygen Potential on the Sulfide Capacity for Slags Containing Multivalent SpeciesManuskript (preprint) (Annet vitenskapelig)
  • 107.
    Allertz, Carl
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Mikro-modellering.
    Kojola, Niklas
    Hui, Wang
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Mikro-modellering.
    A Study of Nitrogen Pickup from the Slag during Waiting Time of Ladle Treatment2014Inngår i: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 85, nr 4, s. 689-696Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An investigation of the nitrogen pickup of liquid steel from ladle slag after vacuum degassing was made. Nitride capacities, C-N, of a number of ladle slags were determined at controlled nitrogen and oxygen potentials at 1873K. The nitride capacities in the composition range studied were found to be very low. In accordance with the literature, the nitride capacity was found to increase with increasing SiO2 content. Industrial trials were performed. The nitrogen content of the steel was determined before and after vacuum degassing as well as after the waiting period. Three different trends of the variation of nitrogen content in the steel were observed. Both the laboratory study and the industrial trials revealed that the transfer of nitrogen from slag to steel was not the reason for nitrogen pickup in the steel subsequent to vacuum degassing.

  • 108.
    Allertz, Carl
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Li, Fan
    White, Jesse F.
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Effect of carbon on the solubility of nitrogen in slag2015Inngår i: International Journal of Materials Research - Zeitschrift für Metallkunde, ISSN 1862-5282, E-ISSN 2195-8556, Vol. 106, nr 8, s. 822-830Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of carbon on nitrogen solubility in slag was investigated for the ternary CaO-MgO-SiO2 and the quaternary Al2O3-CaO-MgO-SiO2 slag systems at 1 873 K under controlled oxygen and nitrogen potentials. Gas-slag equilibration experiments were conducted using molybdenum and graphite crucibles. In the absence of carbon, the nitrogen solubility was very low. The presence of carbon greatly increased the nitrogen solubility in slag. The total nitrogen content was found to increase with SiO2 and MgO concentration for the carbon saturated slags. Low levels of cyanide were found by wet chemistry with considerable uncertainty. The results analyzed by different methods ruled out cyanide formation being the main reason for the large increase in nitrogen solubility in the presence of pure carbon.

  • 109.
    Allertz, Carl
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Selleby, Malin
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    The Effect of Oxygen Potential on the Sulfide Capacity for Slags Containing Multivalent Species2016Inngår i: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 47, nr 5, s. 3039-3045Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The dependence of sulfide capacity on the oxygen partial pressure for slags containing multivalent species was investigated experimentally using a slag containing vanadium oxide. Copper-slag equilibration experiments were carried out at 1873 K (1600 A degrees C) in the approximate oxygen partial pressure range 10(-15.4) to 10(-9) atm. The sulfide capacity was found to be strongly dependent on the oxygen potential in this slag system, increasing with the oxygen partial pressure. The sulfide capacity changed by more than two orders of magnitude over the oxygen partial pressure range. The effect of changing oxygen partial pressure was found to be much greater than the effect of changing slag composition at a fixed oxygen partial pressure.

  • 110.
    Allertz, Carl
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Sichen, Du
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Sulfide Capacity in Ladle Slag at Steelmaking Temperatures2015Inngår i: Metallurgical and materials transactions. B, process metallurgy and materials processing science, ISSN 1073-5615, E-ISSN 1543-1916, Vol. 46, nr 6, s. 2609-2615Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sulfide capacity measurements were conducted at 1823 K and 1873 K (1550 degrees C and 1600 degrees C) for the quaternary Al2O3-CaO-MgO-SiO2 system, for typical compositions used in the ladle in steelmaking. A copper-slag equilibrium was used under controlled oxygen and sulfur potentials. The sulfide capacity is strongly dependent on the composition and it was found to increase with the basic oxides, while it decreases with increase of the acidic components. It was found that CaO is more effective in holding sulfur in the slag compared to MgO when replacing SiO2. For the present slag compositions, Al2O3 and SiO2 behaved similar with respect to sulfur, and no considerable effect could be recorded when replacing one for the other. The sulfide capacity was also found to be strongly dependent on the temperature, increasing with temperature. The present results were compared with industrial data from the ladle, after vacuum treatment, and they were in good agreement.

  • 111.
    Allertz, Carl
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    White, J. F.
    Du, Sichen
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Nitrogen solubility and the effect of carbon in ladle slag at 1873 K2015Inngår i: Proceedings of the 6th International Congress on the Science and Technology of Steelmaking, ICS 2015, Chinese Society for Metals , 2015, s. 316-319Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The solubility of nitrogen in ladle slag was determined at 1873K under controlled nitrogen and oxygen potentials. Gas- slag equilibrium experiments were conducted using molybdenum and graphite crucibles. In the absence of carbon, the nitrogen solubility was very low. The presence of carbon greatly increased the nitrogen solubility in the slag. Low levels of cyanide was detected by wet chemistry, with considerable uncertainty. Cyanide was ruled out as the main reason for the large increase of nitrogen in the presence of pure carbon. The nitrogen solubility was found to increase with increasing SiO2 content both in the absence and presence of carbon.

  • 112. Alm, Hajer Kamal
    et al.
    Ström, Göran
    Karlström, Katarina
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Schoelkopf, Joachim
    Gane, Patrick A. C.
    Effect of excess dispersant on surface properties and liquid interactions on calcium carbonate containing coatings2010Inngår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 25, nr 1, s. 82-92Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of this work was to identify what effects excess amount of sodium polyacrylate, a commonly used dispersant, has on the coating properties and the interaction between ink and the paper coating in offset printing. Since polyacrylate strongly interacts with calcium ions, soluble calcium salt was added to some coating colours to illustrate the impact of charge neutralization by calcium ions. It was found that the coating structure was only slightly affected by the extra addition of polyacrylate, showing some weak flocculation, whereas the surface chemistry was strongly influenced. The coatings became more polar and interacted more strongly with water. This resulted in slower ink setting and reduced ink-paper coating adhesion, especially in the presence of applied water/dampening solution, which are identified as contributory factors in ink piling and print mottle.

  • 113. Almcrantz, M.
    et al.
    Andersson, Margareta A.T.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi.
    Jönsson, Pär G.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi.
    Determination of inclusion characteristics in the Asea-SKF process using the modified spark-induced OES technique as a complement in studying the influence of top slag composition2005Inngår i: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 76, nr 9, s. 624-634Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The spark-induced modified optical emission spectroscopy (OES) technique developed by Ovako Steel makes it possible to rapidly determine inclusion characteristics in steel samples. In earlier investigations using the modified spark-induced OES technique for steel samples taken from billets, predicted oxygen contents agreed well with results from conventional melt extraction analyses. In this investigation, samples taken during ladle treatment in an ASEA-SKF ladle furnace were analysed using the modified OES technique. When comparing the results with inclusion characteristics determined by conventional analysis, similar trends were found. Plant trials were also carried out where three different top slag compositions were used. The purpose was to evaluate if the modified OES technique can be used to study the effect of changes in the refining operation on inclusion characteristics. Results indicated that the modified OES technique could be used to determine the effect of a changed slag composition on the inclusion characteristics in the steel. Since the modified OES method provides rapid feedback of inclusion characteristics, it has the potential of being used for faster optimisation of ladle refining operations.

  • 114. Almgren, Karin
    et al.
    Gamstedt, Kristofer E.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Nygård, P.
    Malmberg, F.
    Lindblad, J.
    Lindström, M.
    Role of fibre-fibre and fibre-matrix adhesion in stress transfer in composites made from resin-impregnated paper sheets.2009Inngår i: International Journal of Adhesion and Adhesives, ISSN 0143-7496, E-ISSN 1879-0127, Vol. 29, nr 5, s. 551-557Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Paper-reinforced plastics are gaining increased interest as packaging materials, where mechanical properties are of great importance. Strength and stress transfer in paper sheets are controlled by fibre-fibre bonds. In paper-reinforced plastics, where the sheet is impregnated with a polymer resin, other stress-transfer mechanisms may be more important. The influence of fibre-fibre bonds on the strength of paper-reinforced plastics was therefore investigated. Paper sheets with different degrees of fibre-fibre bonding were manufactured and used as reinforcement in a polymeric matrix. Image analysis tools were used to verify that the difference in the degree of fibre-fibre bonding had been preserved in the composite materials. Strength and stiffness of the composites were experimentally determined and showed no correlation to the degree of fibre-fibre bonding, in contrast to the behaviour of unimpregnated paper sheets. The degree of fibre-fibre bonding is therefore believed to have little importance in this type of material, where stress is mainly transferred through the fibre-matrix interface.

  • 115.
    Almgren, Karin M.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Träkemi och massateknologi.
    Wood-fibre composites: Stress transfer and hygroexpansion2010Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Wood fibres is a type of natural fibres suitable for composite applications. The abundance of wood in Swedish forests makes wood-fibre composites a new and interesting application for the Swedish pulp and paper industry. For large scale production of composites reinforced by wood fibres to be realized, the mechanical properties of the materials have to be optimized. Furthermore, the negative effects of moisture, such as softening, creep and degradation, have to be limited. A better understanding of how design parameters such as choice of fibres and matrix material, fibre modifications and fibre orientation distribution affect the properties of the resulting composite material would help the development of wood-fibre composites.

    In this thesis, focus has been on the fibre-matrix interface, wood-fibre hygroexpansion and resulting mechanical properties of the composite. The importance of an efficient fibre-matrix interface for composite properties is well known, but the determination of interface properties in wood-fibre composites is difficult due to the miniscule dimensions of the fibres. This is a problem also when hygroexpansion of wood fibres is investigated. Instead of tedious single-fibre tests, more straightforward, macroscopic approaches are suggested. Halpin-Tsai’s micromechanical models and laminate analogy were used to attain efficient interface characteristics of a wood-fibre composite. When Halpin-Tsai’s model was replaced by Hashin’s concentric cylinder assembly model, a value of an interface parameter could be derived from dynamic mechanical analysis. A micromechanical model developed by Hashin was used also to identify the coefficient of hygroexpansion of wood fibres. Measurements of thickness swelling of wood-fibre composites were performed. Back-calculation through laminate analogy and the micromechanical model made it possible to estimate the wood-fibre coefficient of hygroexpansion. Through these back-calculation procedures, information of fibre and interface properties can be gained for ranking of e.g. fibre types and modifications.

    Dynamic FT-IR (Fourier Transform Infrared) spectroscopy was investigated as a tool for interface characterization at the molecular level. The effects of relative humidity in the test chamber on the IR spectra were studied. The elastic response of the matrix material increased relative to the motion of the reinforcing cellulose backbone. This could be understood as a stress transfer from fibres to matrix when moisture was introduced to the system, e.g. as a consequence of reduced interface efficiency in the moist environment. The method is still qualitative and further development is potentially very useful to measure stress redistribution on the molecular level.

    Fulltekst (pdf)
    FULLTEXT01
  • 116.
    Almgren, Karin M.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Träkemi och massateknologi.
    Gamstedt, E. Kristofer
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Träkemi och massateknologi.
    Characterization of interfacial stress transfer ability by dynamic mechanical analysis of cellulose fiber based composite materials2010Inngår i: Composite interfaces (Print), ISSN 0927-6440, E-ISSN 1568-5543, Vol. 17, nr 9, s. 845-861Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The stress transfer ability at the fiber-matrix interface of wood fiber composites is known to affect the mechanical properties of the composite. The evaluation of interface properties at the level of individual fibers is however difficult due to the small dimensions and variability of the fibers. The dynamical mechanical properties of composite and constituents, in this case wood fibers and polylactide matrix, was here used together with micromechanical modeling to quantify the stress transfer efficiency at the fiber-matrix interface. To illustrate the methodology, a parameter quantifying the degree of imperfection at the interface was identified by inverse modeling using a micromechanical viscoelastic general self-consistent model with an imperfect interface together with laminate analogy on the composite level. The effect of moisture was assessed by comparison with experimental data from dynamic mechanical analysis in dry and moist state. For the wood fiber reinforced polylactide, the model shows that moisture absorption led to softening and mechanical dissipation in the hydrophilic wood fibers and biothermoplastic matrix, rather than loss of interfacial stress transfer ability.

  • 117.
    Almgren, Karin M.
    et al.
    Innventia.
    Gamstedt, E. Kristofer
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Träkemi och massateknologi.
    Berthold, Fredrik
    Innventia.
    Lindström, Mikael
    Innventia.
    Moisture uptake and hygroexpansion of wood fiber composite materials with polylactide and polypropylene matrix materials2009Inngår i: Polymer Composites, ISSN 0272-8397, E-ISSN 1548-0569, Vol. 30, nr 12, s. 1809-1816Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Effects of butantetracarboxylic acid (BTCA) modification, choice of matrix, and fiber volume fraction on hygroexpansion of wood fiber composites have been investigated. Untreated reference wood fibers and BTCA-modified fibers were used as reinforcement in composites with matrices composed of polylactic acid (PLA), polypropylene (PP), or a mixture thereof. The crosslinking BTCA modification reduced the out-of-plane hygroexpansion of PLA and PLA/PP composites, under water-immersed and humid conditions, whereas the swelling increased when PP was used as matrix material. This is explained by difficulties for the BTCA-modified fibers to adhere to the PP matrix. Fiber volume fraction was the most important parameter as regards out-of-plane hygroexpansion, with a high-fiber fraction leading to large hygroexpansion. Fiber-matrix wettability during processing and consolidation also showed to have a large impact on the dimensional stability and moisture uptake. POLYM. COMPOS., 30:1809-1816, 2009.

  • 118. Almgren, Karin M.
    et al.
    Gamstedt, E. Kristofer
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Träkemi och massateknologi.
    Varna, Janis
    Luleå tekniska universitet, LTU.
    Contribution of wood fiber hygroexpansion to moisture induced thickness swelling of composite plates2010Inngår i: Polymer Composites, ISSN 0272-8397, E-ISSN 1548-0569, Vol. 31, nr 5, s. 762-771Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    One of the main drawbacks of wood fiber-based composite materials is their propensity to swell due to moisture uptake. Because the wood fibers are usually the main contributor to hygroexpansion, it is of interest to quantify the hygroexpansion coefficient of wood fibers, to compare and rank different types of fibers. This investigation outlines an inverse method to estimate the transverse hygroexpansion coefficient of wood fibers based on measurements of moisture induced thickness swelling of composite plates. The model is based on composite micromechanics and laminate theory. Thickness swelling has been measured on polylactide matrix composites with either bleached reference fibers or crosslinked fibers. The crosslinking modification reduced the transverse hygroexpansion of the composites and the transverse coefficient of hygroexpansion of the fibers was reduced from 0.28 strain per relative humidity for reference fibers to 0.12 for cross-linked fibers

  • 119. Almgren, Karin M.
    et al.
    Åkerholm, Margaretha
    Gamstedt, Kristofer
    Salmén, Lennart
    Lindström, Mikael
    Effects of Moisture on Dynamic Mechanical Properties of Wood Fiber Composites Studied by Dynamic FT-IR Spectroscopy2008Inngår i: Journal of reinforced plastics and composites (Print), ISSN 0731-6844, E-ISSN 1530-7964, Vol. 27, nr 16-17, s. 1709-1721Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wood fiber reinforced polylactide is a biodegradable composite where both fibers and matrix are from renewable resources. In the development of such new materials, information on mechanical behavior on the macroscopic and the molecular level is useful. In this study, dynamic Fourier transform infrared (FT-IR) spectroscopy is used to measure losses at the molecular level during cyclic tensile loading for bonds that are characteristic of the cellulosic fibers and the polylactid matrix. This molecular behavior is compared with measured macroscopic hysteresis losses for different moisture levels. The results show that moisture ingress will transfer the load from the fibers to the matrix, and that a more efficient fiber-matrix interface would diminish mechanical losses. Although the dynamic FT-IR spectroscopy method is still qualitative, this investigation shows that it can provide information on the stress transfer of the constituents in wood fiber reinforced plastics.

  • 120.
    Almjashev, V.I.
    et al.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Barrachin, M.
    Institut de Radioprotection et Suˆrete´ Nucle´aire (IRSN).
    Bechta, Sevostian
    AP Aleksandrov Res Inst Technol, Sosnovyi Bor 188540, Russia.
    Bottomley, D.
    European Commission – DG – Joint Research Centre, Institute for Transuranium Elements.
    Defoort, F.
    Laboratoire de Physico-chimie et Thermohydraulique Multiphasiques (LPTM), CEA/Grenoble, DTN/SE2T/LPTM – 17 rue des Martyrs.
    Fischer, M.
    Framatome ANP GmbH.
    Gusarov, V.V.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Hellmann, S.
    Framatome ANP GmbH.
    Khabensky, V.B.
    A.P. Aleksandrov Research Institute of Technology.
    Krushinov, E.V.
    A.P. Aleksandrov Research Institute of Technology.
    Lopukh, D.B.
    Saint-Petersburg Electrotechnical University ‘LETI’.
    Mezentseva, L.P.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Miassoedov, A.
    Institute for Nuclear and Energy Technologies, Forschungszentrum Karlsruhe.
    Petrov, Yu.B.
    Saint-Petersburg Electrotechnical University ‘LETI’.
    Vitol, S.A
    A.P. Aleksandrov Research Institute of Technology.
    Eutectic crystallization in the FeO(1.5)-UO(2+x)-ZrO(2) system2009Inngår i: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 389, nr 1, s. 52-56Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Results of the investigation of the FeO(1.5)-UO(2+x)-ZrO(2) system in air are presented. The eutectic position and the content of the phases crystallized at this point have been determined. The temperature and the composition of the ternary eutectic are 1323 +/- 7 degrees C and 67.4 +/- 1.0 FeO(1.5), 30.5 +/- 1.0 UO(2+x), 2.1 +/- 0.2 ZrO(2) mol.%, respectively. The solubilities of FeO(1.5) and ZrO(2) in the UO(2+x)(FeO(1.5), ZrO(2)) solid solution correspond to respectively 3.2 and 1.1 mol.%. The solubilities of UO(2) and ZrO(2) in FeO(1.5) are not significant. The existence of a solid solution on the basis of U(Zr)FeO(4) compound is found. The ZrO(2) Solubility in this solid solution is 7.0 mol.%.

  • 121.
    Almjashev, V.I.
    et al.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Barrachin, M.
    Institut de Radioprotection et Suˆrete´ Nucle´aire (IRSN).
    Bechta, Sevostian
    DSAR, AP Aleksandrov Res Inst Technol, NITI, Sosnovyi Bor 188540, Russia .
    Bottomley, D.
    European Commission – DG – Joint Research Centre, Institute for Transuranium Elements.
    Defoort, F.
    Laboratoire de Physico-chimie et Thermohydraulique Multiphasiques (LPTM), CEA/Grenoble, DTN/SE2T/LPTM – 17 rue des Martyrs.
    Fischer, M.
    Framatome ANP GmbH.
    Gusarov, V.V.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Hellmann, S.
    Framatome ANP GmbH.
    Khabensky, V.B.
    A.P. Aleksandrov Research Institute of Technology.
    Krushinov, E.V.
    A.P. Aleksandrov Research Institute of Technology.
    Lopukh, D.B.
    Saint-Petersburg Electrotechnical University ‘LETI’.
    Mezentseva, L.P.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Miassoedov, A.
    Institute for Nuclear and Energy Technologies, Forschungszentrum Karlsruhe.
    Petrov, Yu.B.
    Saint-Petersburg Electrotechnical University ‘LETI’.
    Vitol, S.A
    A.P. Aleksandrov Research Institute of Technology.
    Phase equilibria in the FeO(1+x)-UO(2)-ZrO(2) system in the FeO(1+x)-enriched domain2010Inngår i: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 400, nr 2, s. 119-126Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Experimental results of the investigation of the FeO(1+x)UO(2)-ZrO(2) system in neutral atmosphere are presented. The ternary eutectic position and the composition of the phases crystallized at this point have been determined. The phase diagram is constructed for the FeO(1+x)-enriched region and the onset melting temperature of 1310 degrees C probably represents a local minimum and so will be a determining factor in this system and its application to safety studies in nuclear reactors.

  • 122.
    Almjashev, V.I.
    et al.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Barrachin, M.
    Institut de Radioprotection et Suˆrete´ Nucle´aire (IRSN).
    Bechta, Sevostian
    A.P. Aleksandrov Research Institute of Technology.
    Bottomley, D.
    European Commission – DG – Joint Research Centre, Institute for Transuranium Elements.
    Vitol, S.A
    A.P. Aleksandrov Research Institute of Technology.
    Gusarov, V.V.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Defoort, F.
    Laboratoire de Physico-chimie et Thermohydraulique Multiphasiques (LPTM), CEA/Grenoble, DTN/SE2T/LPTM – 17 rue des Martyrs.
    Krushinov, E.V.
    A.P. Aleksandrov Research Institute of Technology.
    Lopukh, D.B.
    Saint-Petersburg Electrotechnical University ‘LETI’.
    Lysenko, A.V.
    Alexandrov Research Institute of Technology, Federal State Unitary Enterprise.
    Martynov, A.P.
    St. Petersburg Electrotechnical University.
    Mezentseva, L.P.
    Institute of Silicate Chemistry of Russian Academy of Sciences.
    Miassoedov, A.
    Institute for Nuclear and Energy Technologies, Forschungszentrum Karlsruhe.
    Petrov, Yu. B.
    Saint-Petersburg Electrotechnical University ‘LETI’.
    Fischer, M.
    Framatome ANP GmbH.
    Khabensky, V.B.
    A.P. Aleksandrov Research Institute of Technology.
    Hellmann, S.
    Framatome ANP GmbH.
    Ternary eutectics in the systems FeO-UO2-ZrO2 and Fe2O3-U3O8-ZrO212011Inngår i: Radiochemistry, ISSN 1066-3622, Vol. 53, nr 1, s. 13-18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The systems FeO–UO2–ZrO2 (in inert atmosphere) and Fe2O3–U3O8–ZrO2 (in air) were studied. Forthe FeO–UO2–ZrO2 system, the eutectic temperature was found to be 1310°С, with the following componentconcentrations (mol %): 91.8 FeO, 3.8 UO2, and 4.4 ZrO2. For the Fe2O3–U3O8–ZrO2 system, the eutectictemperature was found to be 1323°С, with the following component concentrations (mol %): 67.4 FeO1.5,30.5 UO2.67, and 2.1 ZrO2. The solubility limits of iron oxides in the phases based on UO2(ZrO2,FeO) andUO2.67(ZrO2,FeO1.5) were determined

  • 123. Al-Naamani, Laila
    et al.
    Muthukrishnan, Thirumahal
    Dutta, Joydeep
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Funktionella material, FNM. KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Dobretsov, Sergey
    Antifouling properties or chitosan coatings on plastic substrates2019Inngår i: Journal of Agricultural and Marine Sciences, Vol. 23, nr 1, s. 92-98Artikkel i tidsskrift (Fagfellevurdert)
  • 124.
    Alongi, Jenny
    et al.
    Univ Milan, Dipartimento Chim, Via C Golgi 19, I-20133 Milan, Italy..
    Ferruti, Paolo
    Univ Milan, Dipartimento Chim, Via C Golgi 19, I-20133 Milan, Italy..
    Manfredi, Amedea
    Univ Milan, Dipartimento Chim, Via C Golgi 19, I-20133 Milan, Italy..
    Carosio, Federico
    Politecn Torino, Dipartimento Sci Applicata & Tecnol, Viale Teresa Michel 5, I-15121 Alessandria, Italy..
    Feng, Zhaoxuan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Hakkarainen, Minna
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Polymerteknologi.
    Ranucci, Elisabetta
    Univ Milan, Dipartimento Chim, Via C Golgi 19, I-20133 Milan, Italy..
    Superior flame retardancy of cotton by synergetic effect of cellulose-derived nano-graphene oxide carbon dots and disulphide-containing polyamidoamines2019Inngår i: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321, Vol. 169, artikkel-id 108993Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Linear polyamidoamines containing disulphide groups (SS-PAAs) were prepared by polyaddition of L-cystine with 2,2-bisacrylamidoacetic acid (B-CYSS), N,N'-methylenebisacrylamide (M-CYSS) and 1,4-bisacryloylpiperazine (BP-CYSS). They were evaluated as flame retardants for cotton, alone or with cellulose-derived nano-graphene oxide (nGO) carbon dots, to assess whether, due to their potential as radical scavengers, the latter would improve the already good performance of SS-PAAs. In vertical flame spread tests (VEST), cotton treated with 1% nGO burned as quickly as cotton, whereas B-CYSS, M-CYSS and BP-CYSS extinguished the flame at add-ons >= 12, 16 and 20%, respectively. Probably, the gaseous products of SS-PAA thermal degradation quenched the radicals involved in oxidation. Cotton treated with 8,12 and 15%, respectively, of B-CYSS, M-CYSS and BP-CYSS burned completely, but further addition of 1% nGO either inhibited ignition or shortly extinguished the flame, demonstrating synergism between the two components. Synergism was confirmed by assessing the synergism effectiveness parameter for the residual mass fraction (RMF) and by comparing the calculated and experimental TG curves in air for the cotton/SS-PAA-nGO systems. In cone calorimetry tests, the presence of nGO did not improve the already good performances of SS-PAAs, supporting the hypothesis that the action of both takes place in the gas phase.

  • 125.
    Al-Saadi, Munir
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi.
    Microstructures and mechanical properties: Forged vs rolled bar in Sanmac 22052016Inngår i: Stainless Steel World, ISSN 1383-7184, Vol. 28, nr July/August, s. 45-48Artikkel i tidsskrift (Fagfellevurdert)
  • 126.
    Al-Saadi, Munir
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi.
    Jönsson, Pär
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi.
    Sandberg, Fredrik
    Karasev, Andrey
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Jonsson, Stefan
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Microstructure characterisation in alloy 8252018Konferansepaper (Fagfellevurdert)
  • 127.
    Al-Saadi, Munir
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi.
    Karasev, Andrey
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Jönsson, Pär
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi.
    Sandberg, Fredrik
    Comparative Study of Microstructures Evolution of Columnar and Equiaxed Grain Structurs in Alloy 825 after Hot Compression2018Inngår i: 3rd InternationalConference on Ingot Casting, Rolling and Forging, ICRF2018, in Stockholm, 16-19October, 2018, artikkel-id 114Konferansepaper (Fagfellevurdert)
  • 128.
    Al-Saadi, Munir
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi. R&D, AB Sandvik Materials Technology, SE-811 81Sandviken, Sweden..
    Sandberg, Fredrik
    R&D, AB Sandvik Materials Technology, SE-811 81Sandviken, Sweden..
    Hulme-Smith, Christopher
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi.
    Karasev, Andrey
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi.
    Jönsson, Pär
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Materialens processteknologi.
    A study of the static recrystallization behaviour of cast Alloy 825 after hot-compressions2019Inngår i: Journal of Physics: Conference Series, 2019, Vol. 1270Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The static recrystallization behaviour of a columnar and equiaxed Alloy 825 material was studied on a Gleeble-3800 thermo-simulator by single-hit compression experiments. Deformation temperatures of 1000-1200 °C, a strain of up to 0.8, a strain rate of 1s-1, and relaxation times of 30, 180, and 300 s were selected as the deformation conditions to investigate the effects of the deformation parameters on the SRX behaviour. Furthermore, the influences of the initial grain structures on the SRX behaviors were studied. The microstructural evolution was studied using optical microscopy and EBSD. The EBSD measurements showed a relaxation time of 95 % for fractional recrystallization grains, 𝑡95, in both structures, was less than 30 seconds at the deformation temperatures 1100 °C and 1200 °C. However, fewer than 95% of recrystallized grains recrystallized when the deformation temperature was lowered to 1000 °C. From the grain-boundary misorientation distribution in statically recrystallized samples, the fraction of high-angle grain boundaries decreased with an increasing deformation temperature from 1000 °C to 1200 °C for a given relaxation time. This was attributed to grain coarsening

  • 129.
    Alsaifi, Fadi
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Aging of FeCrAl Surface Coatings2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This Thesis is about the aging of FECRAL surface coatings. In this thesis various substrates have been investigated such as 16 Mo3, 304, 347, Sanicro 31, 800HT, Nikrothal 80 and Kanthal APMT. These substrates have been coated with different FeCrAl alloys, using two different coating methods spraying with (High Velocity Air Force) and welding with (Metal Inert Gas).

    The purpose of coating is to achieve specific properties of the layer without affecting the original properties of the substrate. Therefore, it is important to investigate the boundary layer between these two different materials to observe how the interdiffusion of different substances such as Cr, Al, Fe and C is affected, which is the purpose of this project.

    The method used to investigate this purpose was to expose these combinations in different temperatures and in different environments for different time intervals. Then, using LOM, SEM and EDS analysis, the change that the boundary layers have undergone is examined. Some calculations in DICTRA have also been performed to see if it was possible to find any connection between experimental data and simulation results.

    The result showed carburization of FeCrAl-coatings on 16Mo3 substrates which can lead to deterioration of mechanical properties in the substrates but also decreased corrosion resistance for the coated layers. The result has also shown that it is difficult to perform spraying for small cylindrical products. The reason for this may be the high powder dispersion and the expansion of certain products when spraying, which causes the layer to loosen due to the shrinkage followed by cooling. APMT sprayed with Nikrothal 80 has shown high porosity in the substrates and high interdiffusion of Fe and Ni. High Ni diffusion in low Al alloys such as K 198 may be a reason why the coated layer cannot optimally form the protective oxide.

    Fulltekst (pdf)
    fulltext
  • 130. Altimira, M.
    et al.
    Fuchs, Laszlo
    KTH, Skolan för teknikvetenskap (SCI), Mekanik. KTH, Skolan för teknikvetenskap (SCI), Centra, Linné Flow Center, FLOW.
    Numerical investigation of throttle flow under cavitating conditions2015Inngår i: International Journal of Multiphase Flow, ISSN 0301-9322, E-ISSN 1879-3533, Vol. 75, s. 124-136Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The present paper shows the importance of the resolution of large unsteady flow structures in numerical simulations of cavitating flows. Three-dimensional simulations of the flow through a throttle geometry representative for fuel injectors have been performed to characterise the inception and development of cavitation, adopting the implicit Large Eddy Simulation approach. The two-phase flow has been handled by the Volume of Fluid method; whilst the simplified Rayleigh equation has been adopted to handle bubble dynamics. The mathematical model has been solved in the open source C++ toolbox OpenFOAM 2.0.1. Results obtained with the mathematical model are compared with those from RANS-based simulations and validated against experimental measurements. The performed Large Eddy Simulations not only are able to reproduce vortex cavitation, but also give further insight into the complex interaction between cavitation and turbulence through the assessment of the different terms of the vorticity equation.

  • 131. Altincekic, T. G.
    et al.
    Boz, I.
    Baykal, A.
    Kazan, S.
    Topkaya, R.
    Toprak, Muhammet S.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Materialfysik, Funktionella material, FNM.
    Synthesis and characterization of CuFe2O4 nanorods synthesized by polyol route2010Inngår i: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 493, nr 1-2, s. 493-498Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Uniform, high quality, CuFe2O4 nanorods with high aspect ratios were synthesized by a surfactant-free single step polyol process at 220 degrees C. The structure of the product was characterized by XRD and FT-IR, and the morphology of the product was analyzed by SEM. The results showed that the as-prepared nanorods have a uniform cross-section and with average diameter of similar to 100 nm and aspect ratio in the range of 13-52. X-ray line profile fitting resulted in crystallite size of 15 nm, which reveals the polycrystalline nature of these nanorods. Magnetic characterization of product was performed by EPR and VSM techniques and the results show that the CuFe2O4 nanorods are ferromagnetic. The line width of the resonance lines in FMR is about 1.8 kOe which may originate from different resonance fields of randomly distributed nanocrystals which have different orientation of magnetic easy axes.

  • 132.
    Altzar, Oskar
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Crack initiation in hydro power plant rotor rim sheets: A failure case study for Juktan hydro power plant2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    In 2013, cracks were found in the radius of the dovetail slots of the rotor rim sheets in generator 1 of Juktan hydro power plant in Västerbotten, Sweden. The cracks were estimated to be too deep to be able to repair and Alstom conducted an investigation on the cause of fracture. The investigation came to the conclusion that the radius was too small and that the new rotor rim sheets should have a six times greater fillet radius. However, it has not been investigated whether the material structure or the manufacturing process may have an impact on the crack initiation and following propagation that is the focus of this report.Parts of the dovetail slots were cut out and characterized with XRF, SEM and LOM. Further mechanical characterizations were done according to Vickers.From the SEM and LOM micrographs a high amount of large (10μm) and cubic particles were found in the microstructure. The micrographs also showed a deformation of the microstructure and the hardness test showed a deformation hardening near the edge where the sheet had been punched. The edge surface of the sheet also had notches.The large and hard particles in the microstructure impair the mechanical properties of the steel. Furthermore, the hardening effect combined with the notches will make a good crack initiation point. Therefore, there is a higher possibility that a crack will initiate in the radius of the dovetail slots where large stresses occur.

    Fulltekst (pdf)
    Crack initiation in hydro power plant rotor rim sheets
  • 133.
    Altzar, Oskar
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Mekanisk metallografi.
    Surface Characteristics and Their Impact on Press Joint Strength2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Press fitting is a commonly used method in the assembly of shafts and gearwheels in gearboxes andare using the friction created between them to hold them together. To increase productivity Scania CVAB in Södertälje, Sweden, are going to replace the current hard machining method for layshafts. Whiletesting the new methods in rig it occurred that the gearwheel slipped in tangential direction towardsthe layshaft at a lower torque then with the current method even through all requirements on thelayshafts surface was meet. The purpose and aim with this study is to investigate differences betweenthe methods and to find new requirements for the layshaft. The torque of slip, (Ms) established in atorque test rig and analysis of surface roughness, hardness and microstructure conducted of both thelayshafts and gearwheels. The characteristics of the layshaft surface was also analysed and comparedbetween the different hard machining methods. The study concludes that no correlation between thesurface parameters and the Ms occurred and no major differences in the material between themethods. The study also concluded that the Ms between the layshaft and gearwheel is lower if thelayshaft surface is harder and smoother than the gearwheel surface.

    Fulltekst (pdf)
    fulltext
  • 134. Alvares, E. D.
    et al.
    Botta, W. J.
    Ågren, John
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Costa e Silva, A.
    An assessment of Fe-Nb-B melts using the two-state liquid model2020Inngår i: Calphad, ISSN 0364-5916, E-ISSN 1873-2984, Vol. 68, artikkel-id 101692Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Amorphous alloys of the (Fe-Co-Ni)-(Cr-Mo-Nb)-B system are promising materials to supply the demands for higher wear resistance components in the petrochemical industry. Since the development of the CALPHAD method, the development of new metallic alloys has been accompanied by thermodynamic modelling and calculations. The prediction of the formation of amorphous alloys requires special care with the modeling of the liquid and or an amorphous phase. As a initial stage in the more complex system, the basic Fe-Nb-B ternary system was selected. In order to predict the stability and tendencies of transformations of these amorphous alloys, the Fe-Nb-B system was reassessed using Ågren's two-state model to describe the liquid phase. The results of the present assessment show very good agreement with the recently reported stable phase diagram. Furthermore, the use of the two-state model for the liquid is more accurate and physically consistent when evaluating transformations from supercooled liquid, as shown it the present work.

  • 135.
    Ameen, Ahamed
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Optimization of annealing parameters for SANDVIK 13C26 and 20C strip steels: By MODDE analysis and modified JMAK method2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The process optimization of continuous annealing furnace, RHF 125, for recrystallization annealing of two steel grades, Sandvik 13C26 and Sandvik 20C has been carried out. To recreate the continuous annealing process carried out in the roller hearth furnace in the industry, samples with different cold reduction rates were chosen from ongoing production lines. An experimental heat treatment model was chosen by the ‘Design of Experiments’ approach from MODDE (from U-Metrics). The annealing temperature was chosen below the austenitization temperature for both steel grades and soaking time of 30 seconds to 240 seconds were chosen. Microscopic estimation of fraction recrystallized was performed with the help of Electron Back Scattered Diffraction, accompanied by mechanical testing methods to measure the hardness and yield strength of the steel strips. The experimental output was used to create a model to correlate between the different cold reduction rates and annealing parameters to achieve a higher degree of recrystallization along with desirable mechanical properties. Also, a modified Johnson-Mehl-Avrami-Kolomogrov model, based on hardness values, to determine the transformation kinetics by tracking the progress of recrystallization was developed. The model was verified with EBSD measurements for Sandvik 13C26 strip steels. For 20C, inhomogeneous recrystallization was observed, thus limiting the model’s adaptability to steels which exhibit homogeneous recrystallization behavior and negligible change in precipitation and/or coarsening of secondary phases.

    Fulltekst (pdf)
    fulltext
  • 136.
    Aminlashgari, Nina
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Polymerteknologi.
    Pal, Jit
    Sanwaria, Sunita
    Nandan, Bhanu
    Srivastava, Rajiv K.
    Hakkarainen, Minna
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Degradation product profiles of melt spun in situ cross-linked poly(epsilon-caprolactone) fibers2015Inngår i: Materials Chemistry and Physics, ISSN 0254-0584, E-ISSN 1879-3312, Vol. 156, s. 82-88Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In situ cross-linking of poly(epsilon-caprolactone) (PCL) fiber with bis-(epsilon-caprolactone-4-yl) (BCY) was shown to be a feasible approach to compensate for reduction in molar mass of PCL during melt-spinning. The effect of in situ cross-linking on the degradation profile of melt spun PCL fibers with different amounts of BCY was evaluated using electrospray ionization-mass spectrometry. Degradation of the cross-linked fibers was carried out in aqueous medium at 37 degrees C and 60 degrees C for different periods of time. The degradation profiles were then compared with uncross-linked fiber and 3D porous cross-linked film of PCL Interesting differences in the degradation product profiles with linear, cyclic or BCY-related low molar mass compounds were observed, clearly demonstrating the effect of cross-linking and processing on the degradation process and formation of water-soluble products. In addition the degradation product profiles demonstrated that in situ cross-linking is a feasible technique for counteracting degradation reactions during melt-spinning.

  • 137.
    Aminzadeh, Selda
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Valorization of Kraft Lignin by Fractionation and Chemical Modifications for Different Applications2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Abstract

    Lignin is one of the most abundant biopolymers. Approximately 70 million tons of technical lignin is generated annually, but only little is used for products other than energy. The complexity of lignin hinders full utilization in high-value products and materials. In spite of the large recent progress of knowledge of lignin structure and biosynthesis, much is still not fully understood, including structural inhomogeneity. We made synthetic lignin at different pH’s and obtained structural differences that might explain the structural inhomogeneity of lignin.

    Technical lignins from the chemical pulping are available in large scale, but the processes result in alterations, such as oxidation and condensation. Therefore, to utilize technical lignin, modifications, such as fractionation and/or chemical modifications are necessary. Fractionation with ceramic membranes is one way to lower the polydispersity of lignin. The main advantage is their tolerance towards high temperature and harsh conditions. We demonstrated that low Mw lignin was extracted from industrially produced LignoBoost lignin aiming: i) to investigate the performance of the membrane over time; ii) to analyze the antioxidant properties of the low Mw lignin.

    Chemical modification can also improve the properties of lignin. By adding moieties, different properties can be obtained. Amination and methacrylation of kraft lignin were performed, as well as lignin-silica hybrid materials with potential for the adsorption were produced and investigated.

    Non-modified and methacrylated lignin were used to synthesize lignin-St-DVB porous microspheres to be utilized as a sorbent for organic pollutants. The possibility to substitute styrene with methacrylated lignin was evaluated, demonstrating that interaction between lignin and DVB, and porosity increased.

    Lignin has certain antibacterial properties. Un-modified and modified (aminated) lignin samples and sphere nanoparticles of lignin were tested for their effect against gram-positive and gram-negative bacteria’s and an injectable hydrogel was developed with encapsulated lignin for being used as an injectable gel for the open wounds. Results demonstrated promising antibacterial efficiency of lignins against gram-positive, more especially better inhibition with aminated lignins against gram-positive and negative bacterium.

     

     

    Fulltekst (pdf)
    fulltext
  • 138.
    Aminzadeh, Selda
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Zhang, Liming
    Henriksson, Gunnar
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    A possible explanation for the structural inhomogeneity of lignin in LCC networks2017Inngår i: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 51, nr 6, s. 1365-1376Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lignin has a very complex structure, and this is partly due to the monomers being connected by many different types of covalent bonds. Furthermore, there are multiple covalent bonds between lignin and polysaccharides in wood, and it is known that the structure of lignin covalently bound to the hemicellulose xylan is different to lignin bound to the hemicellulose glucomannan. Here, synthetic lignin (DHP) is synthesized at different pH and it is shown that lignin made at lower pH has a structure more similar to the lignin bound to xylan, i.e., having higher relative content of beta-O-4 ethers. It is hypothesized that xylan due to its carboxylic acids forms a locally lower pH and thus "direct" the lignin structure to have more beta-O-4 ethers. The biological significance of these results is discussed.

  • 139. Amir, M.
    et al.
    Baykal, A.
    Güner, S.
    Sertkol, M.
    Sözeri, H.
    Toprak, Muhammet
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Material- och nanofysik, Funktionella material, FNM.
    Synthesis and Characterization of CoxZn1−xAlFeO4 Nanoparticles2015Inngår i: Journal of Inorganic and Organometallic Polymers and Materials, ISSN 1574-1443, Vol. 25, nr 4, s. 747-754Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nanocrystalline powders of cobalt and aluminum co-substituted zinc ferrites with general formula CoxZn1−xAlFeO4 (x = 0.0–1.0) have been synthesized for the first time. Using the citrate-microwave technique and the citric acid as combustion–complexion agent (fuel), materials with spinel mono-phase cubic spinel structure were successfully prepared. The characterization of products was done by XRD, SEM and VSM. The crystallite size estimated by Scherrer formula has been found in the range of 7.7–9.6 nm. The magnetic properties were studied by room temperature (RT) VSM magnetization measurements. The small remanent magnetization (Mr) and coercivity (Hc) values reveal the superparamagnetic nature of nanoparticles (NPs) at RT. The extrapolated saturation magnetization (Ms) is maximum for Co0.8Zn0.2AlFeO4 (17.15 emu/g) and minimum for ZnAlFeO4 particles (4.22 emu/g). This case is attributed to high or low amount of cation distribution change from normal to mixed spinel structure. The average magnetic diameters (Dmag) were calculated from magnetic fit studies of M–H spectra. Dmag values are between 8.17 and 8.46 nm and this range is in great accordance with the obtained diameters from XRD measurements. The small Mr/Ms ratios (maximum, 0.219) specify the uniaxial anisotropy according to Stoner–Wohlfarth model for CoxZn1−xAlFeO4 NPs. RT effective anisotropy constants (Keff) were calculated by using Ms and Hc values. Keff constants increased with increasing Co content in the spinel NPs.

  • 140. Amirinejhad, S.
    et al.
    Raiszadeh, R.
    Shahid Bahonar Univ Kerman, Dept Met & Mat Sci, Kerman, Iran. Shahid Bahonar Univ Kerman, Mineral Ind Res Ctr, Kerman, Iran..
    Doostmohammadi, Hamid
    Department of Metallurgy and Materials Science and Mineral Industries, Research Centre, Shahid Bahonar University of Kerman, Jomhoori Eslami, Blvd., Kerman, Iran.
    Study of double oxide film defect behaviour in liquid Al-Mg alloys2013Inngår i: International Journal of Cast Metals Research, ISSN 1364-0461, E-ISSN 1743-1336, Vol. 26, nr 6, s. 330-338Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The change in the composition of oxide layers and the possibility of the formation of bonding between the layers of a double oxide film defect when held in Al melts containing 0.7, 1 and 2 wt-%Mg were investigated. The defect was modelled by maintaining two aluminium oxide layers in contact with one another in the melt at 1023 K for times between 5 s and 50 h. Any changes in the composition and morphology of these layers were studied by SEM and energy dispersive X-ray. The results showed that in all the alloys, the initial Al2O3 layer first transformed to MgAl2O4 and then to MgO. These transformations caused the two layers to bond together gradually. The results confirmed that, in all the Al alloys containing 0.3-4.5 wt-%Mg, oxide films have the chance to heal if held in the liquid metal for a long enough period of time.

  • 141.
    Amirinejhad, Sajad
    et al.
    Shahid Bahonar Univ Kerman, Dept Met & Mat Sci, Kerman, Iran.;Shahid Bahonar Univ Kerman, Mineral Ind Res Ctr, Kerman, Iran..
    Raiszadeh, Ramin
    Shahid Bahonar Univ Kerman, Dept Met & Mat Sci, Kerman, Iran.;Shahid Bahonar Univ Kerman, Mineral Ind Res Ctr, Kerman, Iran.;Shahid Bahonar Univ Kerman, Dept Met & Mat Sci, Sch Engn, Kerman, Iran..
    Doostmohammadi, Hamid
    Shahid Bahonar Univ Kerman, Dept Met & Mat Sci, Kerman, Iran.;Shahid Bahonar Univ Kerman, Mineral Ind Res Ctr, Kerman, Iran..
    Calorimetric study of the oxidation of Al-Mg alloys for the prediction of healing of the double oxide film defect2013Inngår i: Journal of thermal analysis and calorimetry (Print), ISSN 1388-6150, E-ISSN 1588-2926, Vol. 113, nr 2, s. 769-777Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The oxidation of Al alloys containing 0.3-4.5 wt% Mg in an atmosphere with a very low oxygen partial pressure (< 0.5 ppm, to depict the atmosphere within a double oxide film defect) was studied using differential scanning calorimetry and scanning electron microscopy. The results showed that a newly formed Al2O3 layer held in an Al-Mg melt first transformed to MgAl2O4 spinel and then to MgO. This mechanism was the same for all the Al alloys containing 0.3-4.5 wt% Mg, but the kinetics of the transformations were different and depended on the Mg content of the melt. The results also suggest that the two layers of a double oxide film defect that is held in an Al melt containing 0.3-4.5 wt% Mg can heal (i.e. bond to each other) if held in the liquid metal for a long enough period of time.

  • 142.
    An, Junxue
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Jin, Chunsheng
    Dedinaite, Andra
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap. SP Technical Research Institute of Sweden.
    Holgersson, Jan
    Karlsson, Niclas G.
    Claesson, Per Martin
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap. SP Technical Research Institute of Sweden.
    Influence of Glycosylation on Interfacial Properties of Recombinant Mucins: Adsorption, Surface Forces, and Friction2017Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 33, nr 18, s. 4386-4395Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Interfacial properties of two brush-with-anchor mucins, C-P55 and C-PSLex, have been investigated at the aqueous solution/poly(methyl methacrylate) (PMMA) interface. Both are recombinant mucin-type fusion proteins, produced by fusing the glycosylated mucin part of P-selectin glycoprotein ligand-1 (PSLG-1) to the Fc part of a mouse immunoglobulin in two different cells. They are mainly expressed as dimers upon production. Analysis of the O-glycans shows that the C-PSLex mucin has the longer and more branched side chains, but C-P55 has slightly higher sialic acid content. The adsorption of the mucins to PMMA surfaces was studied by quartz crystal microbalance with dissipation. The sensed mass, including the adsorbed mucin and water trapped in the layer, was found to be similar for these two mucin layers. Atomic force microscopy with colloidal probe was employed to study surface and friction forces between mucin-coated PMMA surfaces. Purely repulsive forces of steric origin were observed between mucin layers on compression, whereas a small adhesion was detected between both mucin layers on decompression. This was attributed to chain entanglement. The friction force between C-PSLex-coated PMMA is lower than that between C-P55-coated PMMA. at low loads, but vice versa at high loads. We discuss our results in terms of the differences in the glycosylation composition of these two mucins.

  • 143.
    Anantha, Krishnan Hariramabadran
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Örnek, Cem
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Ejnermark, Sebastian
    Medvedeva, Anna
    Sjöström, Johnny
    Pan, Jinshan
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Correlative Microstructure Analysis and In Situ Corrosion Study of AISI 420 Martensitic Stainless Steel for Plastic Molding Applications2017Inngår i: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 164, nr 4, s. C85-C93Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this work, the corrosion behavior of tempered AISI 420 martensitic stainless steel (MSS) was studied by in-situ atomic force microscopy (AFM) in 0.1M NaCl and correlated with the microstructure. Thermocalc simulation, dilatometry, and X-ray diffraction (XRD) were performed to investigate phase transformation which showed the formation of M3C, M7C3, and M23C6 type of carbides and also retained austenite. Optical microscopy, scanning electron microscopy (SEM), and AFM characterization revealed undissolved carbides and tempering carbides in the martensitic matrix. Volta potential mapping measured by scanning Kelvin probe force microscopy (SKPFM) indicated higher electrochemical (practical) nobility of the carbides with respect to the martensitic matrix whereas regions adjacent to carbides showed lower nobilities due to chromium depletion. Open circuit potential and cyclic potentiodynamic polarization measurements showed metastable corrosion activities associated with a weak passive behavior and a risk for localized corrosion along certain carbide boundaries. In-situ AFM measurements revealed selective dissolution of certain carbide interphases and martensitic inter-lath regions indicating higher propensity to localized corrosion.

  • 144.
    Ananthanarayanan, Durga
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap. Katholieke Univ Leuven, Dept Mat Engn, Fac Engn, Kasteelpk Arenberg 44 Bus 2450, BE-3001 Leuven, Belgium..
    Wollants, P.
    Katholieke Univ Leuven, Dept Mat Engn, Fac Engn, Kasteelpk Arenberg 44 Bus 2450, BE-3001 Leuven, Belgium..
    Moelans, N.
    Katholieke Univ Leuven, Dept Mat Engn, Fac Engn, Kasteelpk Arenberg 44 Bus 2450, BE-3001 Leuven, Belgium..
    Phase-field study of IMC growth in Sn-Cu/Cu solder joints including elastoplastic effects2020Inngår i: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 188, s. 241-258Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this article, we aim to study the problem of the growth of intermetallic phases in solder joints undergoing mechanical deformation, using a phase-field model for multi-phase systems that can treat diffusion, elastic and plastic deformation. A suitable model is formulated and applied to Sn-Cu/Cu lead-free solder joints. The growth of the intermetallic layers during solid-state annealing is simulated for different strain states. We assess the values of stiffness tensors available in literature and perform ab initio calculations to support the selection of reasonable values from literature. We also perform a parametric study with different eigenstrain values and applied strains. We find that there is a significant effect of the considered eigenstrains and applied strains on the growth kinetics of the system and parabolic growth kinetics is followed in cases where the intermetallic layers grow. We thereby establish the importance of strain in the growth of intermetallic layers and the need for more targeted experiments on the role of strain in the reliability of the solder joint.

  • 145.
    Anderfors, Mikael
    et al.
    Innventia AB, Sweden.
    Llindström, Tom
    Innventia AB, Sweden.
    On the manufacture of carboxymethylated microfibrillated cellulose from different pulp typesManuskript (preprint) (Annet vitenskapelig)
  • 146.
    Anderfors, Mikael
    et al.
    Innventia AB, Sweden.
    Llindström, Tom
    Innventia AB, Sweden.
    Söderberg, Daniel
    KTH, Skolan för kemivetenskap (CHE), Centra, Wallenberg Wood Science Center. Innventia AB, Sweden.
    The use of microfibrillated cellulose in fine paper manufacturing: Results from a pilot scale papermaking trial2014Inngår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 29, nr 3, s. 476-483Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this work the strength enhancing capabilities of microfibrillated cellulose (MFC) in highly filled papers was studied. Both the MFC production and the paper making were done in pilot scale under realistic industrial conditions. The results clearly show that MFC (2.5 - 5.0wt-%) could improve the mechanical properties of highly filled papers (20 - 35 wt-% filler contents). All studied dry mechanical properties were improved and the improvements were most pronounced for Z-strength and fracture toughness. By combining the MFC with a C-starch dosage further improvements in mechanical properties could be achieved. The improvements in mechanical properties enabled increased filler content with retained properties. The filler increase could be achieved at the same time as the sheet formation and the dry content after pressing were improved.

  • 147. Andersson, A. J.
    et al.
    Andersson, Margareta A.T.
    KTH, Tidigare Institutioner, Materialvetenskap.
    Jonsson, P. G.
    Use of an optimisation model for the burden calculation for the blast furnace process2004Inngår i: Scandinavian journal of metallurgy, ISSN 0371-0459, E-ISSN 1600-0692, Vol. 33, nr 3, s. 172-182Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The aim of a burden calculation in the blast furnace process is to compute the amounts of burden materials to be charged for obtaining desired hot-metal and slag composition. Burden calculations are normally based on trial-and-error instead of optimisation. In this study, the use of an optimisation model for a typical blast furnace operation is presented. The yield factors of some components, such as Mn, Si, S, P and V, used in the model have been determined. The more common distribution coefficients have also been studied. Both the yield factor and distribution coefficient values were generally good and showed stable behaviour for repeated periods under similar operational conditions. In this study, the model was found to be an excellent tool for determining burden material amounts and hot-metal and slag compositions for a blast furnace under steady and normal operation conditions. Using an optimising burden calculation model is time efficient, because it demands only 1 calculation procedure instead of a couple calculations as in the case with a trial-and-error method.

  • 148.
    Andersson, Annika
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi.
    Andersson, Margareta A.T.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi.
    Jönsson, Pär G
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi.
    A study of some elemental distributions between slag and hot metal during tapping of the blast furnace2004Inngår i: Steel research, ISSN 0177-4832, Vol. 75, nr 5, s. 294-301Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper investigates the distribution of elements between slag and hot metal from a blast furnace through calculation of distribution coefficients from actual production data. First, samples of slag and hot metal tapped from a commercial blast furnace were taken continually at 10-minute intervals for a production period of 68 hours. Distribution coefficients of manganese, silicon, sulphur and vanadium were then calculated from the results of the sample analyses. A major conclusion drawn from examination of the results was that the behaviour of the studied elements was as could be expected when approaching the equilibrium reactions from thermodynamic theory. The distributions of the elements in the slag-metal system showed clear tendencies which did not appear to be influenced by the operational conditions of the furnace. For example, for manganese, vanadium and sulphur, it was found that a higher basicity led to a decreased distribution coefficient L-Mn and L-V, but an increased L-S, which is according to theory. Another observed relationship was that slag basicity increased with an increased carbon content in the hot metal, which indicated that SiO2 was reduced to [Si] when the oxygen potential decreased. Furthermore, it was found that sulphur and silica behaviour likened that of acidic slag components, while the manganese oxide and vanadium oxide behaviour was similar to that of basic slag components.

  • 149. Andersson, Annika J.
    et al.
    Andersson, Margareta A. T.
    KTH, Tidigare Institutioner, Materialvetenskap.
    Jönsson, Pär G.
    KTH, Tidigare Institutioner, Materialvetenskap.
    Variation in hot metal and stag composition during tapping of blast furnace2004Inngår i: Ironmaking & steelmaking, ISSN 0301-9233, E-ISSN 1743-2812, Vol. 31, nr 3, s. 216-226Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To determine the quality of the hot metal and the thermal conditions inside the blast furnace, the composition of the hot metal and slag must be known. Obtaining representative metal and slag samples during tapping is thus highly important to blast furnace operation. The study covered in the present report focused on hot metal and slag composition variation during tapping from a commercial blast furnace. From the results, optimal sampling time points for obtaining elemental concentrations that can be taken as representative for the whole tapping sequence were identified. It was furthermore concluded, that the reliability of hot metal composition data is significantly improved by averaging elemental concentrations determined from two samples, each taken at a particular time point. One sampling, however, was found to be adequate for slag. Results from the study also showed a fairly strong correlation between amounts of silicon and carbon, sulphur and carbon, and silicon and sulphur in the hot metal, while a weaker correlation between hot metal temperature and each of these elements was observed.

  • 150.
    Andersson, Axel
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Built-up edge formation in stainless steel milling2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Milling tests were performed in stainless steel to investigate the formation of built-up edge (BUE). Three variants of tests were conducted which were divided as high-, medium, and low temperature milling tests. These tests were run in the austenitic stainless steel SS2343. The medium temperature milling tests were run in duplex SS2343 and precipitation hardened CORRAX. BUE was found for all tests. With the exception of the high temperature milling tests, BUE was formed locally on the main cutting edge. When milling at higher temperature the BUE covered the entire edge. All inserts used, each with different technologies had the same amount of BUE formation. The tool wear was similar for the CVD-coated inserts used, while the PVD-coated insert suffered less coating detachment along the edge.

     

    Cross sections showed that in addition to BUE, smearing had occurred on the rake face of the inserts, showing that multiple layers of material adhered to the tool surface. Cross sections also showed that the tool wear was similar for the different milling methods, even though it was known that tool failure eventually would be caused by different wear types.

     

    Microhardness tests of the BUE gave results where the austenitic- and duplex stainless steel had in average almost doubled their hardness. Work hardening for CORRAX was lower with an average hardness increase below 9 percent. As CORRAX gave the same amount of BUE formation as the other steels it could be concluded that work hardening did not affect the amount of BUE formation.

     

    For one sample milled at high temperature a new phase had formed on the insert surface. Analysis in EPMA and EDS indicated that it contained chromium, manganese and oxygen. This indicated that the stainless steel had oxidized when milled at higher temperature. When comparing the composition, it was similar for both BUE and the workpiece material SS2343. The only exception was that titanium could be found in the bulk of the BUE, having higher amount when milled at higher temperature. This indicated that the BUE had interacted with the coating, as this was the only source of titanium.

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