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  • 1.
    Hou, Zi Yong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap. Northeastern University, China.
    Wu, Di
    Zheng, Shu Xin
    Yang, Xiao Long
    Li, Zhuang
    Xu, Yun Bo
    Effect of Holding Temperature on Microstructure and Mechanical Properties of High-Strength Multiphase Steel2016Ingår i: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 87, nr 9, s. 1203-1212Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Isothermal holding following intercritical annealing is usually used in microstructure control, e.g., fractions and stabilities of retained-austenite (RA). Fe-0.22C-2.5Mn-0.47Si-0.41Cr-0.02Nb (mass%) steel is subjected to intercritical annealing and isothermal treatment at 250, 300, 350, and 400 degrees C to elucidate the impact on microstructures and mechanical properties by means of electron microscopy and uniaxial tensile test, respectively. The results show that the isothermal holding temperature is vital for the formed phases, including the morphology, volume fraction, and carbon content of RA in the processed steels. The tensile test results indicate that the mechanical properties including Ultra-tensile strength (UTS), Yield strength (YS), as well as Total Elongation (TEL) are attributed to the synthetic action of all constituents of phase morphology and corresponding fractions, e.g., hard-to-soft phase ratio, morphology and fraction of RA, dispersed precipitates. An excellent combination of strength-ductility of the present multiphase steel has been explained in terms of their specific microstructure.

  • 2.
    Hou, Ziyong
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    An experimental and theoretical study of precipitation during tempering of martensite in Fe-C-Cr alloys2018Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
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  • 3.
    Hou, Ziyong
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Study of precipitation in martensitic Fe-C-Cr alloys during tempering: Experiments and modelling2015Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Understanding the precipitation reaction is very important since precipitation hardening is one of the most effective strengthening mechanisms in metallic alloys. In martensitic steels, a tempering heat treatment is often performed. During tempering various new phases are precipitated and the spatial and temporal evolution of these precipitates strongly influences the properties of the steel, such as strength/ductility, creep, fatigue and hot corrosion resistance. Therefore, the possibility of quantitative modelling of the precipitation process will provide many opportunities for advanced materials and process design and optimization as well as service life assessments. The Fe-C-Cr system forms the basis for tool steels and is consequently used in many applications such as e.g. metal forming operations. They are characterized by a high hardness and good toughness, even at elevated temperatures.In the present work, the as-quenched martensitic microstructures of four Fe-C-Cr alloys with varying Cr and C contents were characterized by Light Optical Microscopy (LOM) and Electron Microscopy. The effects of Cr and C on the morphology of martensite were investigated. It was found that Cr addition had a similar effect as C on the martensitic morphology and on the ratio of high-angle grain boundary (HAGB) to low-angle grain boundary (LAGB). However, the micro-hardness was unaffected by the Cr addition whilst it was strongly influenced by the C addition.In addition, a quantitative experimental characterization of the precipitates formed during tempering of the martensite was performed. The Langer-Schwartz theory combined with the Kampmann-Wagner-Numerical (KWN) method, as implemented in the software TC-PRISMA, was used to predict the precipitation of carbides after tempering in one of the model alloys: Fe-0.15C-4.0Cr (mass%). The microstructure characterization of the as-quenched material provided vital input parameters for the modelling work and a comparison was made between the modelling predictions and the experimental results. The effect of parameters such as dislocation density, grain size and interfacial energy on the precipitation of carbides was discussed.

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    Thesis
  • 4.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Babu, Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Odqvist, Joakim
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Coarsening of cementite during tempering of a martensitic steelManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Coarsening of cementite (M3C) in a martensitic steel alloy Fe–1C–1Cr (wt. %) during tempering at 700 °C was investigated by electron microscopy and kinetic modelling. It is shown that the large M3C carbides are mostly located at high-angle grain boundaries in the coarsening stage and simple kinetic simulations predict the experimentally observed mean size evolution well when grain boundary diffusion of Cr is taken into account. However, the particle size distribution of M3C maintain a log-normal distribution throughout the whole extended tempering process (5000 h at 700 °C), which indicates that a modified LSW distribution , as predicted by classical steady-state coarsening theory , is not fully adequate for practical purposes in tempering of martensitic steels.

  • 5.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Babu, Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Odqvist, Joakim
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Early stages of cementite precipitation during tempering of 1C-1Cr martensitic steelManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    The precipitation of cementite (M3C) from as-quenched martensite during tempering at 500 and 700 °C was investigated in a Fe–1C–1Cr (wt. %) alloy. Tempering for a short duration at 700 °C results in a Cr/Fe ratio in the core region of M3C precipitates which is equal to the bulk alloy composition, while a shell on the surface of the precipitates exhibit a higher Cr concentration. With a prolonged tempering up to 5 hours, the shell concentration gradually increases towards the equilibrium value but the core region has not yet reached the equilibrium value. After tempering for 5 seconds at 500 °C, there is no Cr enrichment found at the M3C/matrix interface, while a transition to partitioning of Cr is found during the first 5 minutes of tempering at 500 °C. These experimental results indicate that M3C grows without significant partitioning of substitutional elements at both temperatures initially, i.e. growth is carbon diffusion controlled. This stage is, however, very short, and soon after 5 seconds at 700 °C and 5 min at 500 °C, Cr diffusion becomes important. Calculations using the diffusion simulation software DICTRA and precipitation simulation software TC-PRISMA were performed. The diffusion simulations using the local equilibrium interface condition show excellent agreement with experiments concerning Cr enrichment of the particles, but the size evolution is overestimated. On the other hand, the precipitation simulations underestimate the size evolution. It is suggested that a major improvement in the precipitation model could be achieved by implementing a modified nucleation model that considers nucleation far from the equilibrium composition.

    Ladda ner fulltext (pdf)
    fulltext
  • 6.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Babu, Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Xu, Yunbo
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Wu, Di
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Enhanced Grain Growth Behavior of Ferritic Steel during Continuous Cyclic Annealing2018Ingår i: Steel Research International, ISSN 1611-3683, E-ISSN 1869-344X, Vol. 89, nr 11, artikel-id 1800222Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Microstructural characterization as well as mechanical property determination of a cold-rolled ferritic steel subjected to isothermal and cyclic non-isothermal annealing, has been carried out by utilizing comprehensive experimental analysis. The findings show that the variables of cyclic annealing, that is, amplitude, ramp rate, and intermediate holding time exhibit a great effect on the grain growth kinetics and the evolution of grain boundaries. The resulting grain size of the cyclic annealed steel is mainly attributed to the following factors: 1) the accelerating effect in the grain growth behavior caused by the additional driving force available during cyclic annealing, which increases with increasing amplitude; 2) the retarding effect due to the low equivalent isothermal temperature. Furthermore, the formation of low sigma- coincidence site lattice (sigma CSL) boundaries and the strength of gamma-fiber texture are enhanced through the cyclic annealing compared to the isothermal annealing. The potential advantages of continuous cyclic annealing in the steel industry are explored, in comparison with the conventional isothermal and cyclic annealing with an intermediate soaking time.

  • 7.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Babu, R. Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Odqvist, Joakim
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Early stages of cementite precipitation during tempering of 1C-1Cr martensitic steel2019Ingår i: Journal of Materials Science, ISSN 0022-2461, E-ISSN 1573-4803, Vol. 54, nr 12, s. 9222-9234Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The precipitation of cementite (M3C) from as-quenched martensite during tempering at 500 and 700 degrees C was investigated in a Fe-1C-1Cr (wt%) alloy. Tempering for a short duration at 700 degrees C results in a Cr/Fe ratio in the core region of M3C precipitates which is equal to the bulk alloy composition, while a shell on the surface of the precipitates exhibits a higher Cr concentration. With a prolonged tempering up to 5h, the shell concentration gradually increases toward the equilibrium value, but the core region has not yet reached the equilibrium value. After tempering for 5s at 500 degrees C, there is no Cr enrichment found at the M3C-matrix interface, while a transition to partitioning of Cr is found during the first 5min of tempering at 500 degrees C. These experimental results indicate that M3C grows without significant partitioning of substitutional elements at both temperatures initially, i.e., growth is carbon diffusion controlled. This stage is, however, very short, and soon after 5s at 700 degrees C and 5min at 500 degrees C, Cr diffusion becomes important. Calculations using the diffusion simulation software DICTRA and precipitation simulation software TC-PRISMA were performed. The diffusion simulations using the local equilibrium interface condition show excellent agreement with experiments concerning Cr enrichment of the particles, but the size evolution is overestimated. On the other hand, the precipitation simulations underestimate the size evolution. It is suggested that a major improvement in the precipitation model could be achieved by implementing a modified nucleation model that considers nucleation far from the equilibrium composition.

  • 8.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap. Northeastern Univ, State Key Lab Rolling & Automat, Shenyang 110819, Liaoning, Peoples R China.
    Babu, R. Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Odqvist, Joakim
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Microstructure evolution during tempering of martensitic Fe-C-Cr alloys at 700 A degrees C2018Ingår i: Journal of Materials Science, ISSN 0022-2461, E-ISSN 1573-4803, Vol. 53, nr 9, s. 6939-6950Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The microstructure evolution of two martensitic alloys Fe-0.15C-(1.0 and 4.0) Cr (wt%) was investigated, using X-ray diffraction, electron backscatter diffraction, electron channeling contrast imaging and transmission electron microscopy, after interrupted tempering at 700 A degrees C. It was found that quenching of 1-mm-thick samples in brine was sufficient to keep most of the carbon in solid solution in the martensite constituent. The high dislocation density of the martensite decreased rapidly during the initial tempering but continued tempering beyond a few minutes did not further reduce the dislocation density significantly. The initial martensitic microstructure with both coarse and fine laths coarsened slowly during tempering for both alloys. However, a clear difference between the two alloys was distinguished by studying units separated by high-angle boundaries (HABs). In the low-Cr alloy, M3C precipitates formed and coarsened rapidly, thus they caused little hindrance for migration of HABs, i.e., coarsening of the HAB units. On the other hand, in the high-Cr alloy, M7C3 precipitates formed and coarsened slowly, thus they were more effective in pinning the HABs than M3C in the low-Cr alloy, i.e., coarsening of HAB units was minute in the high-Cr alloy.

  • 9.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi. Northeastern University, China.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Chen, Q.
    Xu, Y.
    Wu, D.
    Odqvist, Joakim
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Quantitative modeling and experimental verification of carbide precipitation in a martensitic Fe-0.16 wt%C-4.0 wt%Cr alloy2016Ingår i: Calphad, ISSN 0364-5916, E-ISSN 1873-2984, Vol. 53, s. 39-48Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Precipitation of carbides during tempering of a martensitic Fe-0.16 wt% C-4.0 wt% Cr alloy has been investigated by experimental analysis and quantitative modeling. It is found that both M7C3 and M23C6 form, at low- and high-angle grain boundaries in the martensite, as well as, at dislocations inside individual laths of martensite, during tempering at 700 °C. The applied Kampmann-Wagner numerical (KWN) modeling, utilizing CALPHAD thermodynamic and kinetic databases together with an assumption of local equilibrium and a constant tie-line, captures the main features of the precipitation, with a transient formation of metastable M23C6, and with M7C3 as the stable carbide. The predicted volume fraction and size are in reasonable agreement with extraction experiments for M7C3. However, for the metastable minority carbide M23C6, the modeling underestimates the size and overestimates the volume fraction within the transient time. With sound thermodynamic databases and physical parameter input, the adopted simplified modeling scheme is a valuable tool for materials design and optimization. Furthermore, by treating conditions at the phase interface more rigorously it is possible to account for different mechanisms of precipitation, such as e.g., non-partitioning local equilibrium, which could be important in systems where interstitial elements diffuse much faster than the substitutional ones.

  • 10.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi. Northeastern University, China .
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Chen, Qing
    Xu, Yunbo
    Di, Wu
    Odqvist, Joakim
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi. AB Sandvik Materials Technology, RandD Centre, Sweden .
    Quantitative modeling and experimental verification of carbide precipitation in a martesnsitic Fe-0,16 wt.%C-4.0 wt.%Cr alloyManuskript (preprint) (Övrigt vetenskapligt)
  • 11.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi. Northeastern University, China .
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Xu, Yunbo
    Di, Wu
    Odqvist, Joakim
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi. AB Sandvik Materials Technology, RandD Centre, Sweden .
    Microstructure of Martensite in Fe-C-Cr and its Implications for Modelling of Carbide Precipitation during Tempering2014Ingår i: ISIJ International, ISSN 0915-1559, E-ISSN 1347-5460, Vol. 54, nr 11, s. 2649-2656Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The microstructure of as-quenched martensite in four Fe-C-Cr alloys (0.15C-1Cr, 0.15C-4Cr, 1C-1Cr, 1C-4Cr, mass%) has been investigated. Moreover, the microstructures served as input for setting up modeling of carbide precipitation during tempering of martensite. The modelling was conducted using the Langer-Schwartz approach and the software TC-PRISMA, which retrieves thermodynamic data from the Thermo-Calc databank. It was found that the martensite in the low carbon steels is predominantly lath martensite with units arranged parallel to each other. On the other hand, the plate martensite dominates the microstructure in the high carbon steels. The ratio of high-angle to low-angle grain boundaries was found to increase with increasing Cr in the low carbon steels, which indicates that Cr has a similar effect as C on the lath martensite microstructure, however, the micro-hardness remained unaffected by the addition of Cr. Finally, the precipitation modeling clearly demonstrates the importance of proper definition of the initial microstructure for predictive modelling. Parameters such as dislocation density and frequency of high-angle grain boundaries have a drastic effect on e.g. the mean size of carbides.

  • 12.
    Hou, Ziyong
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Linder, David
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Ström, Valter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Holmström, E.
    Sandvik Coromant R&D, SE 126 80 Stockholm, Sweden.
    Borgenstam, Annika
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Evaluating magnetic properties of composites from model alloys – Application to alternative binder cemented carbides2019Ingår i: Scripta Materialia, ISSN 1359-6462, E-ISSN 1872-8456, Vol. 168, s. 96-99Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The magnetic properties of 85Ni-15Fe model alloys containing Co, W and C have been studied with the intent to isolate the influence of alloy chemistry on quality control measurements of alternative binder cemented carbides. The results show a strong influence of dissolved W on the Curie temperature and the saturation magnetization. The amount of dissolved C, and the presence of WC precipitates, on the other hand, is shown to have negligible effect. Furthermore, the magnetic coercivity is indicated to be entirely dominated by the microstructural features and quite insensitive to composition.

  • 13.
    Hou, Ziyoung
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Wu, D.
    Odqvist, Joakim
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Study of carbide precipitation during tempering of martensite in an Fe-Cr-C alloy2015Ingår i: PTM 2015 - Proceedings of the International Conference on Solid-Solid Phase Transformations in Inorganic Materials 2015, International Conference on Solid-Solid Phase Transformations in Inorganic Materials , 2015, s. 685-686Konferensbidrag (Refereegranskat)
  • 14.
    Linder, David
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hou, Ziyong
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Xie, Ruiwen
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Ström, Valter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Holmström, Erik
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Borgenstam, Annika
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    A comparative study of microstructure and magnetic properties of a Ni–Fe cemented carbide: Influence of carbon content2019Ingår i: International Journal of Refractory Metals and Hard Materials, ISSN 0263-4368, Vol. 80, s. 181-187Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to the renewed interest in alternative binders for cemented carbides it is important to understand how the binder composition influences not only mechanical properties but also the microstructure and related measurements for quality control. Microstructure and chemical composition of WC-Co is often evaluated by magnetic measurements. However, when the binder composition deviates significantly from conventional Co-based binders it should not be assumed that the standard measurements can be used to directly evaluate the same parameters. In this paper we investigate the influence of relative C-content on the microstructure and magnetic properties of an alternative binder cemented carbide. It is shown that the saturation magnetization is related to the relative C-content and the magnetic coercivity is related to the microstructure, more specifically to the binder phase distribution, but could not be directly linked to the carbide grain size in the same manner as for standard WC-Co. Furthermore, a direct correlation between Curie temperature and saturation magnetization is observed for this system which means that the Curie temperature potentially could be used for calibration of empirical relations or as a method to accurately determine the binder volume fraction.

  • 15.
    Wang, Wei
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap. Dept Chemical Engineering, Northeast Electric Power University, Jilin, 132012, China.
    Hou, Ziyong
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi.
    Lizarrága, Raquel
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Tian, Ye
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Babu, Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Holmström, Erik
    Coromant R & D, SE-12680, Stockholm, Sweden.
    Mao, Huahai
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap. Thermo-Calc Software, Råsundav. 18, SE-16767, Solna, Sweden.
    Larsson, Henrik
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Metallografi. Thermo-Calc Software, Råsundav. 18, SE-16767, Solna, Sweden.
    An experimental and theoretical study of duplex fcc+hcp cobalt based entropic alloys2019Ingår i: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 176, s. 11-18Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Martensitically formed duplex fcc + hcp Co-based entropic alloys have been investigated both experimentally and theoretically. Theoretical predictions are in good agreement with experimental observations. A fair correlation is found between calculated driving forces for a partitionless fcc→hcp transformation and experimentally obtained phase fractions.

    Ladda ner fulltext (pdf)
    fulltext
  • 16.
    Xie, Ruiwen
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad materialfysik.
    Lizárraga, Raquel
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Linder, David
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hou, Ziyong
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Ström, Valter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Lattemann, M.
    Holmström, E.
    Li, Wei
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Vitos, Levente
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Quantum mechanics basis of quality control in hard metals2019Ingår i: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 169, s. 1-8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Non-destructive and reliable quality control methods are a key aspect to designing, developing and manufacturing new materials for industrial applications and new technologies. The measurement of the magnetic saturation is one of such methods and it is conventionally employed in the cemented carbides industry. We present a general quantum mechanics based relation between the magnetic saturation and the components of the binder phase of cemented carbides, which can be directly employed as a quality control. To illustrate our results, we calculate the magnetic saturation of a binder phase, 85Ni15Fe binary alloy, using ab-initio methods and compare the theoretical predictions to the magnetic saturation measurements. We also analyse interface and segregation effects on the magnetic saturation by studying the electronic structure of the binder phase. The excellent agreement between calculations and measurements demonstrates the applicability of our method to any binder phase. Since the magnetic saturation is employed to ensure the quality of cemented carbides, the present method allows us to explore new materials for alternative binder phases efficiently.

  • 17.
    Zhou, Tao
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Babu, Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hou, Ziyong
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Odqvist, Joakim
    KTH, Tidigare Institutioner (före 2005), Materialvetenskap.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Precipitation of multiple carbides in martensitic CrMoV steels -experimental analysis and exploration of alloying strategy through thermodynamic calculationsManuskript (preprint) (Övrigt vetenskapligt)
    Publikationen är tillgänglig i fulltext från 2020-12-31 17:36
  • 18.
    Zhou, Tao
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hou, Ziyong
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Babu, Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Hedström, Peter
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Recent developments in transmission electron microscopy based characterization of precipitation in metallic alloysManuskript (preprint) (Övrigt vetenskapligt)
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