The kinetics and cellular automaton modeling of dynamic recrystallization behavior of a medium carbon Cr-Ni-Mo alloyed steel in hot working process

详细信息    查看全文

• 作者：Chi Zhang^a ; ^b ; Liwen Zhang^a ; ^{commat@mail.dlut.edu.cn" class="auth_mail" title="E-mail the corresponding author} ; Qianhong Xu^a ; Yingnan Xia^a ; Wenfei Shen^a
• 关键词：Medium carbon steel ; Hot deformation ; Dynamic recrystallization ; Cellular automaton
• 刊名：Materials Science & Engineering A
• 出版年：2016
• 出版时间：15 December 2016
• 年：2016
• 卷：678
• 期：Complete
• 页码：33-43
• 全文大小：7170 K

文摘

The dynamic recrystallization (DRX) behavior of a medium carbon Cr-Ni-Mo alloyed steel 34CrNiMo was studied in the wide temperature range of 900–1150 °C and the strain rate of 0.002–5 s⁻¹. Based on relations between the strain hardening rate and stress, the characteristic points, including critical strain (ε_c${\epsilon }_c$), critical stress (σ_c${\sigma }_c$), peak strain (ε_p${\epsilon }_p$), peak stress (σ_p${\sigma }_p$), were determined from the strain rate hardening versus stress curves. The Avrami equation was developed to model the kinetics of DRX, whereas the characteristic points can be expressed as a function of Zener-Hollomon parameter. Then the austenite grain size of DRX was measured by metallography and found to be a power law function of Zener-Hollomon parameter with an exponent of −0.2013. Besides, a mesoscopic cellular automaton model has been established to simulate the austenite DRX for the tested steel. This model was verified by means of the kinetics and topology of DRX.