Modeling Research on Influence of Alloy Design on Bainite Transformation Kenitics

doi:10.12068/j.issn.1005-3026.2022.11.006

Abstract

Abstract: A kinetic model of bainite isothermal transformation based on nucleation-controlled mechanism was used to study the effect of alloy design on bainite transformation kinetics. Using two kinds of high-strength bainite steels， isothermal bainite transformation experiments were conducted at 425~350℃ with a dilatometer. Different degrees of incomplete phase transformation phenomenon are observed. Based on nucleation-controlled mechanism， the displacive transformation kenetic model was used to describe the bainite isothermal transformation behavior of two experimental steels， where grain-boundary nucleation and autocatalytic nucleation were both considered. Finally， the difference in activation energy of nucleation， volume fraction of untransformed austenite and the nucleation rate etc between two experimental steels were comparatively analyzed， which provide theoretical guidance for the composition design and process innovation of high-strength bainite steel.

Key words: bainite; isothermal transformation; transformation kenitics; displacive mechanism; ultra-high strength steel

CLC Number:

TG142.1

LI Mei-ying， XIAO Nai-you， ZHOU Jian-hua， JIA Tao. Modeling Research on Influence of Alloy Design on Bainite Transformation Kenitics[J]. Journal of Northeastern University(Natural Science), 2022, 43(11): 1561-1569.

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