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  • 1.
    Aune, Ragnhild, E
    et al.
    KTH, Superseded Departments, Metallurgy.
    Seetharaman, Seshadri
    KTH.
    Experimental studies of heat capacities of Nd2Fe17, Nd2Fe17N1.49 and Nd2Fe17N1.75 alloys in the temperature range 273-773 K1998In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 17, no 4, p. 299-311Article in journal (Refereed)
  • 2.
    Aune, Ragnhild E.
    et al.
    KTH, Superseded Departments, Materials Science and Engineering.
    Sridhar, S.
    Hayashi, Miyuki
    Viscosities and Gibbs energies: On a common structural base2004In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 22, no 5/6, p. 369-378Article in journal (Refereed)
    Abstract [en]

    The present paper reviews the extensive work carried out with respect to the modeling of viscosities of high temperature melts carried out in the Division of Metallurgy, Royal Institute of Technology (KTH), Stockholm, Sweden. This work was inspired to a great extent by a past collaboration with Professor Ken Mills at Imperial College, London, UK. A thermodynamic approach based on Richardson's theory of ideal mixing of silicates, was used to predict the viscosities of binary silicates. The second derivative of In eta with respect to composition was used to predict the setting of ordering in a homogeneous silicate melt during cooling as it approaches the liquidus temperature. The paper clearly demonstrates the powerfulness of the thermodynamic approach to physical properties of high temperature melts.

  • 3. Bjorkvall, J.
    et al.
    Du, S. C.
    Seetharaman, Seshadri
    KTH, Superseded Departments, Materials Science and Engineering.
    Thermodynamic description of 'FeO'-MgO-SiO2 and 'FeO'-MnO-SiO2 melts - a model approach2000In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 19, no 1, p. 49-59Article in journal (Refereed)
    Abstract [en]

    Activities of the oxide components in the 'FeO'-MgO-SiO2 and 'FeO'-MnO-SiO2 systems have been predicted based on the information of binary systems using a thermodynamic model. The model considers the ionic melt as an oxygen-ion matrix with the cations including Si4+ distributed in it. The interactions between different cations in the presence of O2- are considered as functions of both composition and temperature. The activities predicted by the model are in good agreement with the experimental data available in the literature.

  • 4.
    Björklund, Johan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Andersson, Margareta
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Jönsson, Pär
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    The Influence of Vacuum Treatment on Inclusion Composition: Laboratory Study2010In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 29, no 3, p. 189-202Article in journal (Refereed)
    Abstract [en]

    A series of lab scale trials have been carried out with the aim of investigating the effect of vacuum treatment on inclusion chemistry. A ball bearing steel grade (1.47 wt% Cr, 0.96 wt% C) has been melted in a controlled atmosphere in magnesia and alumina crucibles. A laboratory vacuum furnace, which makes it possible to carry out sampling during vacuum treatment, was used. Samples were taken before and during vacuum treatment. Thereafter, the inclusion compositions in the samples were determined using SEM in combination with EDS. The inclusions found were mainly sulphides containing both manganese and chromium. In addition to these, MgO-Al2O3 oxides were found with varying contents of calcium. Furthermore, a few, calcium sulphides were found. Additionally, it was possible to find a small difference in the average inclusion composition in the samples taken before and during vacuum. More specifically, it was seen that the composition of the inclusions becomes more sulphide-rich during vacuum treatment. The change of average inclusion composition was not as large as suggested from theoretical computations and oxides were found at the same extent during vacuum as before. Another finding was that the inclusions from the trial where an alumina crucible was used contained no magnesia, but that the inclusions contained magnesia when a magnesia crucible was used. Even though the effect of vacuum treatment on the inclusion compositions was found to be small, it was concluded that vacuum treatment could not to be neglected when studying inclusions influenced by top slag/metal reactions.

  • 5.
    Björklund, Johan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Andersson, Margareta
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Jönsson, Pär
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    The Influence of Vacuum Treatment on Inclusion Composition: Theoretical Study2010In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 29, no 3, p. 179-187Article in journal (Refereed)
    Abstract [en]

    A theoretical study has been conducted into how inclusion composition is influenced by vacuum treatment. Software for computational thermodynamics has been used to simulate how the conditions in a steel melt changed as a result of a decreased pressure. A case study was made on a low sulphur bearing steel (1.4% Cr, 1.0%C). The calculations show the effect of sulphur, oxygen, carbon and temperature on precipitated phases in the steel melt. The result shows that at low pressure, formation of carbon monoxide takes place. For 5 ppm O and 10 ppm S the CO-gas becomes thermodynamically stable below 40 torr. Oxide phases will be reduced and CaS will be the stable phase.

  • 6. Brooks, R.
    et al.
    Egry, I.
    Ricci, E.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Wunderlich, R.
    Thermophysical property measurements of high-temperature liquid metallic alloys - State of the art2006In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 25, no 06-maj, p. 303-322Article in journal (Refereed)
    Abstract [en]

    In this report, a survey is presented about state-of-the-art thermophysical property measurements of liquid metallic: alloys at high temperatures. Methods for measuring both caloric quantities, like specific heat and thermal conductivity, and thermophysical properties, like density, surface tension and viscosity, are described in detail. Measurement techniques discussed include container-based as well as containerless techniques. Strengths and potential pitfalls in applying these methods are pointed out and recommendations for best-practice are given.

  • 7. Formenti, A.
    et al.
    Eliasson, Anders
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Ceramics.
    Mitchell, A.
    Fredriksson, Hasse
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Processing.
    Solidification sequence and carbide precipitation in Ni-base superalloys IN718, IN625 AND IN9392005In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 24, no 4, p. 239-258Article in journal (Refereed)
    Abstract [en]

    Differential Thermal Analysis (DTA) and Directional Solidification and Quenching (DSQ) were used to evaluate the solidification and precipitation sequence for the Ni-base superalloys IN718, IN625 and IN939. They all showed a similar precipitation sequence, with an initial precipitation of gamma dendrites, followed by an intermediate non-invariant divorced eutectic reaction of type L -> gamma + MC, and a final eutectic precipitation of Laves phase for alloy IN718 and IN625 and of eta-phase for alloy IN939. The reaction temperatures and the amounts of carbides and of final precipitates were evaluated. Precipitated nitrides were found to act as nucleation sites for the precipitation of blocky carbides/carbonitrides, at low interdendritic supersaturation, while in interdendritic regions with high supersaturation, a 'script-like' carbide formation was found instead.

  • 8.
    Formenti, Angelo
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Eliasson, Anders
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Ceramics.
    Fredriksson, Hasse
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Processing.
    On the dendritic growth and microsegregation in Ni-base superalloys IN718, IN625 and IN9392005In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 24, no 4, p. 221-238Article in journal (Refereed)
    Abstract [en]

    Directional Solidification and Quenching (DSQ) has been used to analyse the solidification, segregation and precipitation behaviour of the Ni-base alloys IN718, IN625 and IN939. The microsegregation in the primary solidified gamma-phase was analysed by Energy Dispersive Spectroscopy (EDS) and were mainly found to be Nb for alloy IN718 and Ti for alloy IN939. The microsegregation behaviour were analysed by numerical back diffusion models and it was found that the diffusion rate in the samples was higher than expected from the theory. A suggested explanation was that this was an effect of the formation of lattice defects during the solidification process. The coarsening process that occurs during the further cooling of the samples is proved to be by the mechanism of back diffusion i.e. the smaller secondary dendrite arms grow together with the thicker ones into a plate.

  • 9.
    Jönsson, Pär
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Aune, Ragnhild E.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Du, Sichen
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Micro-Modelling.
    Teng, Lidong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Matsushita, Taishi
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Sundberg, Sven
    The Seetharaman Seminar June 14-15, 2010 in Stockholm, Sweden2012In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 31, no 3, p. 193-193Article in journal (Other academic)
  • 10. Lahiri, A. K.
    et al.
    Yogambha, R.
    Dayal, P.
    Seetharaman, Seshadri
    KTH, Superseded Departments, Materials Science and Engineering.
    Foam in iron and steelmaking2004In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 22, no 06-maj, p. 345-351Article in journal (Refereed)
    Abstract [en]

    Foam is common in iron and steelmaking processes. Iron and steelmaking slags have inherent foaminess but the presence of strong surface active compounds like P2O5, Cr2O3, CaS, V2O5 and CaF2 make the foam more stable. Stable foam can form only in the presence of surface active agents. When a bubble rises on the surface of a liquid, the film around it develops a concentration gradient of surface active agents such that Marangoni force acts in upward direction. This prevents liquid drainage from the film. The presence of surface active agents favours fort-nation of smaller bubbles and prevents bubble rupture as well. So a strong surface active agent where dsigma/dc is high makes the foam very stable. When a bubble comes into contact with a solid surface, the dynamic contact angle is different from the equilibrium value. If the former is less than the latter, there is a resultant outward force which tries to make the bubble flat. This force is responsible for the collapse of foamy slags in the presence of large carbonaceous particles. This force is not significant for very small bubbles and is not effective when carbon particles are much smaller than the bubble.

  • 11.
    Lindbergh, Göran
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Sparr, M.
    Electrochemical performance of the porous nickel anode in the molten carbonate fuel cell2001In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 20, no 04-mar, p. 313-318Article in journal (Refereed)
    Abstract [en]

    In this study, stationary polarisation curves were obtained for a porous nickel electrode under varying temperatures and anode gas compositions. The exchange current densities were determined from the slopes of the polarisation curves at low overpotentials, i.e. the assumption was made that the porous electrode is under kinetic control. The outlet gas compositions were measured by analysis in a gas chromatograph. The gases were found to be far from equilibrium. However, almost the same reaction orders were found independently of the assumptions of gas compositions but they were rather high and therefore difficult to explain by the generally assumed mechanisms.

  • 12.
    Matsushita, Taishi
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    ThermoLab project: Results on Thermophysical Properties Data of Iron Alloys2008In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 27, no 6, p. 413-421Article in journal (Refereed)
    Abstract [en]

    As a part of ThermoLab project, the thermophysical properties of industrially important iron alloys were measured. In this paper, the measurement results of the differential scanning calorimetry (DSC), specific heat capacity, thermal diffusivity, surface tension and viscosity of one Fe-Cr and of a low oxygen eutectoid manganese steel are reported. In addition to the ground based experiments, parabolic flights (microgravity) experiments with a non-contact electromagnetic levitation device were employed for surface tension and viscosity measurements.

  • 13. Mis, M.
    et al.
    Sardana, N.
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    The Synthesis and Characterization of Ni-W-C Alloy Powders by H-2-CH4 Reaction with Oxides2008In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 27, no 4, p. 209-222Article in journal (Refereed)
    Abstract [en]

    With a view to developing a more energy-efficient and environment-friendly process route for the production of W-C based cutting tools, a single step process for the synthesis of tungsten carbides containing Ni from oxide precursors was investigated in the present work. A fluidized bed reactor was employed, wherein the mixed oxides were subjected to simultaneous reduction and carburization using H-2-CH4-Ar gas mixtures in the temperature range 1073-1273 K. The carbon potential in the gas phase could be accurately controlled by suitably adjusting the H-2/CH4 ratio. The impact of gas flow rates and temperature on the reaction product was examined. The carbide product obtained was characterized by SEM and X-ray diffraction. The results showed that the product consisted of Ni-W-C alloys, which were in consistency with the phase diagram at the temperature of reaction. The particle size of the carbides is in the range of 10(-8)m, which was dependent on the process temperature, higher temperature yielding larger grains. The results indicate that the gas-solid reaction route combining reduction and carburization is an efficient method that can be commercially applied for the production of a variety of cemented carbides.

  • 14.
    Mu, Wangzhong
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering. McMaster University, Canada.
    Jönsson, Pär
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Nakajima, Keiji
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Recent Aspects on the Effect of Inclusion Characteristics on the Intragranular Ferrite Formation in Low Alloy Steels: A Review2017In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 36, no 4, p. 309-325Article in journal (Refereed)
    Abstract [en]

    Intragranular ferrite (IGF), which nucleates from specific inclusion surfaces in low alloy steels, is the desired microstructure to improve mechanical properties of steel such as the toughness. This microstructure is especially important in the coarse grain heat affected zone (CGHAZ) of weldments. The latest review paper focusing on the role of non-metallic inclusions in the IGF formation in steels has been reported by Sarma et al. in 2009 (ISIJ int., 49(2009), 1063-1074). In recent years, large amount of papers have been presented to investigate different issues of this topic. This paper mainly highlights the frontiers of experimental and theoretical investigations on the effects of inclusion characteristics, such as the composition, size distribution and number density, on the IGF formation in low carbon low-alloyed steels, undertaken by the group of Applied Process Metallurgy, KTH Royal Institute of Technology. Related results reported in previous studies are also introduced. Also, plausible future work regarding various items of IGF formation is mentioned in each section. This work aims to give a better control of improving the steel quality during casting and in the heat affected zone (HAZ) of weldment, according to the concept of oxide metallurgy.

  • 15.
    Muhmood, Luckman
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Semykina, Anna
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Iwase, Masanori
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Some Novel Studies of Thermodynamics, Kinetics and Transport Phenomena in Slags2012In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 31, no 4-5, p. 351-358Article in journal (Refereed)
    Abstract [en]

    The following paper revolves around the research work conducted in collaboration during Professor Iwase's brief visits to the Materials Process Science Division at Royal Institute of Technology, Stockholm. The paper focuses on the thermodynamic aspects of CaOFeO-SiO2 and CaO-FeO-SiO2-MnO slag oxidation in air and sulfur transport through CaO-Al2O3-SiO2 slag. Thermodynamics of slag oxidation in air opens potential new areas in terms of focus on effective recovery of iron oxide from slag. The slag transport studies are of fundamental nature and focuses on a novel technique to calculate the diffusion of species through slag by analyzing its corresponding concentration in the metal phase.

  • 16. Nagata, K.
    et al.
    Fukuyama, H.
    Taguchi, K.
    Ishii, H.
    Hayashi, Miyuki
    KTH, Superseded Departments, Materials Science and Engineering.
    Thermal Conductivity of Molten Al, Si and Ni Measured under Microgravity2004In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 22, no 5-6, p. 267-273Article in journal (Refereed)
    Abstract [en]

    The thermal conductivities of molten Si, Ni, Al and their alloys have been measured by means of the nonstationary hot wire method under 1 G and microgravity of 10-5 G. A Mo wire was used as the heating wire and coated with alumina by the electrophoretic deposition to prevent an electric current leakage through the melts. Natural convection in the melts was suppressed by measuring the thermal conductivity under the microgravity of 10-5 G using the drop shaft facility of the Japan Microgravity Center. Moreover, the free surface of the melts was covered with a ceramics plate to prevent Marangoni flow. The thermal conductivity of molten Si is about 10 Wm-1K-1, and that of molten Al is 47 Wm -1K-1 at 1260 K. The thermal conductivity of molten Al-30 mass% Si alloy is about 30 Wm-1K-1, and that of molten Ni is 5 Wm-1K-1 at 1773 K. The thermal conductivities of some molten metals are discussed on the deviation from the Wiedemann-Franz law.

  • 17.
    Nakajima, Keiji
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Wang, Qiang
    Preface to the Special Issue on "Cutting Edge of Computer Simulation of Solidification, Casting and Refining"2017In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 36, no 4, p. 307-308Article in journal (Refereed)
  • 18.
    Seetharaman, Seshadri
    et al.
    KTH, Superseded Departments, Materials Science and Engineering.
    Sichen, Du
    KTH, Superseded Departments, Materials Science and Engineering.
    Eriksson, R.
    Kapilashrami, E.
    Static and dynamic thermophysical property measurements at high temperatures2004In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 22, no 06-maj, p. 283-290Article in journal (Refereed)
    Abstract [en]

    In view of the importance of generating reliable and self consistent thermophysical data, efforts have been made in the Division of Metallurgy, Royal Institute of Technology, Stockholm to measure the viscosities and thermal diffusivities of multicomponent slags as well as surface- and interfacial tensions. The measurements were also carried out in the dynamic mode to monitor high temperature reactions and understand the underlying mechanisms. In the latter case, the rate of dissolution of alumina in a slag as well as the rate of oxidation of Fe2+ in a fayalite slag were followed by measuring the viscosities along the reaction coordinate. The reaction rate between liquid iron with different oxygen levels and alumina/silica substrates was studied by the sessile-drop method. The paper illustrates the usefulness of this approach in understanding high temperature phenomena.

  • 19.
    Söder, Mats
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Jönsson, Pär
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Jonsson, Lage
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Process Metallurgy.
    Growth of Small Alumina Clusters during Ladle Deoxidation2009In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 28, no 6, p. 347-368Article in journal (Refereed)
    Abstract [en]

    For the first time, the size distribution of small clusters was determined in a systematic manner from samples taken during deoxidation with aluminium in an induction-stirred ladle. Chemical and microscopic analyses of samples were performed. The results indicated rapid cluster growth throughout the experiment and at the end of the experiment a majority of the small inclusions were found to be bound in clusters. The cluster growth was concluded to be by collision. Growth-model calculations were carried out to verify the experimental findings. In order to perform these calculations, a method first needed to be developed for conversion of the experimental data determined per unit area to data given per unit volume. Next, the cluster collision diameter was modelled using a theory for fractal aggregates. The results from the growth-model calculations, simulating deoxidation with aluminium, were found to agree well with the experimental results.

  • 20. Tinoco, J.
    et al.
    Fredriksson, Hasse
    KTH, Superseded Departments, Materials Science and Engineering.
    Solidification of a modified Inconel 625 alloy under different cooling rates2004In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 23, no 1, p. 13-24Article in journal (Refereed)
    Abstract [en]

    The solidification characteristics of a modified version of Inconel 625 alloy were studied under nonequilibrium conditions. To achieve this, samples were melted and then solidified under cooling rates ranging from 0.1 K/s to 8000 K/s using a modified DTA, a mirror furnace and levitation casting. Features such as solidification interval and latent heat of fusion were obtained from the cooling curves. The segregation patterns of a number of alloy elements were analysed as well as the amount of the different phases found in the microstructure. Three reactions were observed in the DTA thermographs, i.e. precipitation of austenite, niobium carbides and Laves. eutectic. The measured latent heat of fusion is not constant along the solidification process. Lower values of latent heat of fusion were measured as high cooling rates. The segregation behavior of the different solute elements indicates that the cooling rate promotes higher concentrations in solid solution. The amount of secondary phases decreases with increasing cooling rate. A theoretical explanation is given in terms of lattice defects formed in the solid and their interaction with the solute atoms.

  • 21.
    Wang, Haijuan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Viswanathan, Nurni N.
    Ballal, N. Bharath
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Modeling of Reactions between Gas Bubble and Molten Metal Bath-Experimental Validation in the Case of Decarburization of Fe-Cr-C melts2009In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 28, no 6, p. 407-419Article in journal (Refereed)
    Abstract [en]

    A theoretical generic model describing the mass transfer phenomena between rising gas bubbles and a metal bath has earlier been developed by the present authors, to predict the composition change in the melt as consequence of blowing different oxidant gases. In order to verify the model predictions, a series of experiments involving reactions between Fe-Cr-C melts and different O(2)-CO(2) gas mixtures were carried out. The results showed that the decarburization deviates significantly from thermodynamic paths predicted on the basis of bulk compositions and that the model was able to make reasonably reliable predictions of the changes of chromium and carbon contents in the melt as a function of time. According to the model, the compositions at the vicinity of injection point as well as at the gas-melt interface in the bubble are likely to be far from that in the bulk. The results of the present set of experiments showed, with CO(2) injection, the utilization of the available oxygen for decarburization was higher as compared to O(2) injection in the case of melts containing higher carbon levels (>1mass%). Reverse is the case in low carbon melts. The results also indicate relatively less Cr-losses from the metal bath when CO(2) is used as the oxidant. As the model predictions are found to be reasonably reliable, the model predictions are extended to predict the impact of the variation of different process parameters.

  • 22.
    Wang, Lijun
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    Chou, Kuo-chih
    Seetharaman, Seshadri
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Materials Process Science.
    A new method for evaluating some thermophysical properties for ternary system2008In: High Temperature Materials and Processes, ISSN 0334-6455, E-ISSN 2191-0324, Vol. 27, no 2, p. 119-126Article in journal (Refereed)
    Abstract [en]

    In our earlier papers, we have presented a new method, named the mass triangle model, for calculating physicochemical properties in the ternary system within a limited solubility area. This model was shown to be superior to traditional geometrical models in the computation of ternary data from the known data for the corresponding binaries. In the present paper, the authors extend this method to a ternary system where the entire compositional area inside the ternary triangle is homogeneous. The successful application of this new method to the estimation of surface tension and density has been demonstrated in the case of the system Ni(3)S(2)-FeS-Cu(2)S at 1473K with mean square root error of +/- 1.83%, +/- 4.33% respectively, compared with the experimental results.

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