Model of Phase Transformation for Niobium Microalloyed Steels

Archives of Metallurgy and Materials

M. Pietrzyk¹  B. Niżnik² 

[1] Faculty of Metals Engineering and Industrial Computer Science Department of Physical and Powder Metallurgy, AGH University of Science and Technology, 30-059 Kraków, 30 Mickiewicza Av., Poland;Institute For Ferrous Metallurgy, 44-100 Gliwice, 12-14 K. Miarki Str., Poland

关键词: Keywords: niobium microalloyed steels;    model of phase transformation;    carbonitride precipitation process;    thermomechanical treatment;    multiscale modelling;   

DOI  :  10.2478/v10172-011-0081-1

学科分类：金属与冶金

来源: Akademia Gorniczo-Hutnicza im. Stanislawa Staszica / University of Mining and Metallurgy

【 摘 要 】

The paper presents the results of physical and numerical modeling of the kinetics of phase transformation, taking into account the precipitation of niobium carbonitride. Strain induced precipitation is a phenomenon, which controls the evolution of the microstructure in these steels during thermo-mechanical treatment. For the numerical simulation of precipitation Dutta-Sellars model was used, which describes the precipitation kinetics of Nb (C, N) at dislocations in the deformed and non-deformed austenite. The size of precipitates after continuous cooling of steel was calculated using the additivity rule. Numerical model combines a solution of the finite element method with model of phase transitions. Physical modeling included dilatometric study and rolling of rods made of niobium microalloyed steel. Microstructure studies were also carried out. Developed model allowed the assessment of the influence of precipitation on the progress of phase transition. Verification of model prediction by comparison with the experiments carried out in conditions close to semi-industrial is described in the paper, as well.

【 授权许可】

Unknown