TY - JOUR
T1 - Thermodynamic Modelling and Microstructural Study of Z-Phase Formation in a Ta-Alloyed Martensitic Steel
AU - Riedlsperger, Florian Kerem
AU - Gsellmann, Bernadette
AU - Povoden-Karadeniz, Erwin
AU - Tassa, Oriana
AU - Matera, Susanna
AU - Dománková, Mária
AU - Kauffmann, Florian
AU - Kozeschnik, Ernst
AU - Sonderegger, Bernhard
PY - 2021/3/2
Y1 - 2021/3/2
N2 - A thermokinetic computational framework for precipitate transformation simulations in Ta-containing martensitic Z-steels was developed, including Calphad thermodynamics, diffusion mobility data from the literature, and a kinetic parameter setup that considered precipitation sites, interfacial energies and dislocation density evolution. The thermodynamics of Ta-containing subsystems were assessed by atomic solubility data and enthalpies from the literature as well as from the experimental dissolution temperature of Ta-based Z-phase CrTaN obtained from differential scanning calorimetry. Accompanied by a comprehensive transmission electron microscopy analysis of the microstructure, thermokinetic precipitation simulations with a wide-ranging and well-documented set of input parameters were carried out in MatCalc for one sample alloy. A special focus was placed on modelling the transformation of MX into the Z-phase, which was driven by Cr diffusion. The simulation results showed excellent agreement with experimental data in regard to size, number density and chemical composition of the precipitates, showing the usability of the developed thermokinetic simulation framework.
AB - A thermokinetic computational framework for precipitate transformation simulations in Ta-containing martensitic Z-steels was developed, including Calphad thermodynamics, diffusion mobility data from the literature, and a kinetic parameter setup that considered precipitation sites, interfacial energies and dislocation density evolution. The thermodynamics of Ta-containing subsystems were assessed by atomic solubility data and enthalpies from the literature as well as from the experimental dissolution temperature of Ta-based Z-phase CrTaN obtained from differential scanning calorimetry. Accompanied by a comprehensive transmission electron microscopy analysis of the microstructure, thermokinetic precipitation simulations with a wide-ranging and well-documented set of input parameters were carried out in MatCalc for one sample alloy. A special focus was placed on modelling the transformation of MX into the Z-phase, which was driven by Cr diffusion. The simulation results showed excellent agreement with experimental data in regard to size, number density and chemical composition of the precipitates, showing the usability of the developed thermokinetic simulation framework.
KW - thermodymics
KW - precipitate kinetics
KW - microstructure
KW - modelling
KW - steel
KW - creep
KW - Thermodynamics
KW - Precipitate kinetics
KW - Creep
KW - Modelling
KW - Microstructure
KW - Steel
UR - http://www.scopus.com/inward/record.url?scp=85103011491&partnerID=8YFLogxK
U2 - 10.3390/ma14061332
DO - 10.3390/ma14061332
M3 - Article
VL - 14
JO - Materials
JF - Materials
SN - 1996-1944
IS - 6
M1 - 1332
ER -