摘要
为探究TWIP钢高温条件下的塑性变形机理,建立了耦合温度效应的晶体塑性本构模型,考虑温度对TWIP钢滑移和孪生的影响,提出了耦合温度效应的流动法则和硬化法则。结合在500℃和750℃条件下的原位SEM高温拉伸试验,建立了描述TWIP钢热变形过程的晶体塑性有限元模型。模拟获得不同温度条件下的应力应变曲线、应变硬化率和孪晶体积分数与试验结果相吻合,验证了该模型的正确性。进而,基于所建立的模型研究了温度对TWIP钢塑性变形过程滑移、孪生演化及应变硬化过程的影响规律,结果表明:滑移阻力、孪生阻力和应变硬化率随温度的升高呈不均匀降低的趋势,且断后伸长率呈现降低的趋势,由25℃时53.4%降低至750℃时16.5%。同时,随温度升高,孪生受到抑制,但滑移受温度的影响较小,表现为滑移主导的塑性变形机制。
In order to investigate the deformation mechanism of TWIP steel at high temperature,the crystal plastic constitutive model was established by considering the effect of temperature on slip and twinning of TWIP steel,and the flow law and hardening law of considering temperature effect were proposed.The crystal plastic finite element model of TWIP steel during hot deformation was established by in-situ SEM high temperature tensile tests under 500℃ and 750℃.The stress-strain curves,strain hardening rates and twin volume fraction at different temperatures obtained by simulation were in agreement with the experimental results,which verified the correctness of the model.Based on the model,the effect of temperature on the slip,twinning and strain hardening of TWIP steel during plastic deformation was researched,the results show that the slip resistance,twinning resistance and strain hardening rate decrease unevenly with the increase of temperature,and the elongation after breaking decreases abnormally,from 53.4% at 25℃ to 16.5% at 750℃.With the increase of temperature,the twinning is restrained while the slip process is less affected by temperature,which shows the plastic deformation mechanism dominated by slip.
作者
蔡旺
王春晖
孙朝阳
马晋遥
李月敏
姜军
张跃飞
CAI Wang;WANG Chunhui;SUN Chaoyang;MA Jinyao;LI Yuemin;JIANG Jun;ZHANG Yuefei(School of Mechanical and Engineering,University of Science and Technology Beijing,Beijing 100083;Beijing Key Laboratory of Lightweight Metal Forming,Beijing 100083;Institute of Microstructure and Property of Advanced Materials,Beijing University of Technology,Beijing 100124;Department of Mechanical Engineering,Imperial College London,London,SW72AZ UK)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2022年第20期283-293,共11页
Journal of Mechanical Engineering
基金
国家自然科学基金委员会与英国皇家学会合作交流(51911530209)
国家自然科学基金委员会-中国工程物理研究院NSAF联合基金(U1730121)
中央高校基础科研业务费(FRF-BD-20-08A,FRF-AT-20-09,FRF-GF-19-003A)
国家自然科学基金基础科学中心(51988101)资助项目。
关键词
TWIP钢
塑性变形
晶体塑性
温度效应
原位SEM高温拉伸
TWIP steel
plastic deformation
crystal plasticity
temperature effect
in-situ SEM high temperature tensile
