TWIP钢低温塑性变形机理的原位电镜研究  

In situ TEM investigation on cryogenic deformation mechanism of twinning⁃induced plasticity steel

作　　者：符晓倩 余倩 陈江华 FU Xiaoqian;YU Qian;CHEN Jianghua(Pico Electron Microscopy Center,Innovation Institute for Ocean Materials Characterization Technology,Center for Advanced Studies in Precision Instruments,Hainan University,Haikou Hainan 570228;Center of Electron Microscopy,State Key Laboratory of Silicon and Advanced Semiconductor Materials,School of Material Science and Engineering,Zhejiang University,Hangzhou Zhejiang 310027,China)

机构地区：[1]海南大学精密仪器高等研究中心,海洋材料表征技术创新研究院,皮米电子显微镜中心,海南海口570228 [2]浙江大学材料科学与工程学院,硅及先进半导体材料全国重点实验室,电子显微镜中心,浙江杭州310027

出　　处：《电子显微学报》2024年第1期61-67,共7页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金资助项目(No.52201145).

摘　　要：本文采用透射电镜中的原位低温拉伸测试技术,进行了-50℃、-120℃及-180℃下孪晶诱导塑性变形(TWIP)钢均匀塑性变形阶段的变形缺陷行为分析,研究了温度变化对于TWIP钢中的位错滑移与孪生行为的影响。研究发现,TWIP钢在-50℃下激活了常规滑移之外的其它滑移系;随着温度的进一步降低,TWIP钢中位错活性未发生明显下降,特别是需要热激活辅助的位错交滑移在-180℃下仍可发生。同时研究结果说明,低温下TWIP钢强塑性的保持由多种变形机制共同协调作用:形变孪生、孪晶与位错相互作用、位错交滑移及其引起的位错相互作用,本质是其孪生行为与位错滑移的活性同时得到了保持。Using in situ straining tests in transmission electron microscopy,we investigate the deformation behavior of twinning⁃induced plasticity deformation steel during uniform plastic deformation stages at-50℃、-120℃and-180℃,and analyze the dependence of temperature on the dislocation slip and twinning behaviors.It is found that at-50℃,in addition to general slip systems in TWIP steel,extra slip system is activated;and with the decrease of temperature,the dislocation activities in TWIP steel behave similarly to that at room temperature,especially the cross slip of dislocation requiring thermal activation could still occur at-180℃.The result indicates that the maintenance of ability of twinning and dislocation slip at cryogenic temperature renders the TWIP steel deforming by coordination of multiple deformation mechanisms,including deformation twinning,cross⁃slip of dislocation,dislocation interaction promoted by cross⁃slip.

关 键 词：TWIP钢 原位电镜 低温变形 位错滑移 形变孪生 

分 类 号：O77[理学—晶体学] TG115[金属学及工艺—物理冶金]