应力对中碳超细晶贝氏体钢显微组织的影响  

Effect of stress on microstructure of a medium-carbon ultrafine grain bainitic steel

作　　者：周明星[1] 余可多 周书翊 李瑞智 王佳豪 汪子健 ZHOU Ming-xing;YU Ke-duo;ZHOU Shu-yi;LI Rui-zhi;WANG Jia-hao;WANG Zi-jian(The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学耐火材料与冶金国家重点实验室,湖北武汉430081

出　　处：《材料热处理学报》2024年第6期84-91,共8页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(52004192);中国博士后科学基金(2021M692488);河北省自然科学基金(E2022318018);武汉科技大学大学生创新创业训练计划项目(D202305082148204930)。

摘　　要：贝氏体相变过程中经常会受到应力/应变的影响,其相变动力学和显微组织将发生显著改变。采用热模拟试验机、扫描电镜、透射电镜、电子背散射衍射技术等研究了应力对一种中碳超细晶贝氏体钢显微组织的影响。结果表明:随着应力的增大,贝氏体板条厚度先增加后减小。应力提供的额外机械驱动力导致贝氏体板条粗化,而奥氏体变形则有利于细化板条,两者相互竞争造成了上述现象。此外,通过对比实验极图和理论计算极图发现,在本实验条件下,奥氏体与贝氏体之间更符合Nishiyama-Wassermann(N-W)取向关系。施加应力后,贝氏体变体种类显著减少,产生明显变体选择。The bainite transformation process is often affected by stress and/or strain,and its transformation kinetics and microstructure will undergo significant changes.The effect of stress on microstructure of a medium carbon ultrafine grain bainitic steel was studied by means of thermal simulation testing machines,scanning electron microscopy,transmission electron microscopy and electron backscatter diffraction techniques.The results show that the thickness of bainite lath first increases and then decreases with the increase of stress.The additional mechanical driving force provided by the stress leads to the coarsening of bainite lath,while the deformation of austenite is conducive to the refinement of bainite lath.The competition between the two causes the above phenomenon.In addition,by comparing the experimental and theoretical calculated pole figures,it is found that under the experimental conditions,the relationship between austenite and bainite is more in line with the Nishiyama-Wassermann(N-W)orientation relationship.After applying stress,the number of bainite variants significantly decreases,resulting in a significant selection of variants.

关 键 词：贝氏体 显微组织 晶体学 应力 

分 类 号：TG142.3[一般工业技术—材料科学与工程]