超级贝氏体组织中的应力诱发相变研究  

Stress-induced phase transformation of super bainite microstructure

作　　者：修文翠[1,2] 吴化 韩英[1] 郭明阳[3] 刘云旭 XIU Wencui;WU Hua;HAN Ying;GUO Mingyang;LIU Yunxu(Key Laboratory of Advanced Structural Materials of Ministry of Education,Changchun University of Technology,Changchun 130012,China;School of Mechanical and Civil Engineering,Jilin Agricultural Scienceand Technology University,Jilin 132101,China;Jilin Midas AluminiumCo.Ltd.,Liaoyuan 136200,China)

机构地区：[1]长春工业大学先进结构材料省部共建教育部重点实验室,吉林长春130012 [2]吉林农业科技学院机械与土木工程学院,吉林吉林132101 [3]吉林麦达斯铝业有限公司,吉林辽源136200

出　　处：《哈尔滨工程大学学报》2019年第6期1115-1121,共7页Journal of Harbin Engineering University

基　　金：国家自然科学基金项目(51171030);吉林农业科技学院青年基金项目(2017214);现代农业机械化与信息化创新团队资金

摘　　要：为了研究钢中超级贝氏体产生应力诱发相变对其组织和力学性能的影响,将60Mn2SiCr钢经完全奥氏体化后,在250℃~270℃盐浴炉中等温处理获得超级贝氏体,并通过在疲劳试验机上施加不同的拉-拉交变载荷来探讨其对实验钢力学性能的影响。使用SEM、TEM和XRD对样品分别进行组织形貌观察和相组成的确定。显微组织中部分残余奥氏体发生应力诱发相变,转变为孪晶马氏体,致使钢的强塑积提高近32.4%。结果表明:超级贝氏体中的部分残余奥氏体能够通过产生应力诱发相变改善钢的强韧性。The effect of stress-induced transformation of super bainite on its structure and mechanical properties in steel was investigated.A typical super bainite microstructure was obtained in experimental steel 60Mn2SiCr through a full austenitization process and subsequent isothermal treatment at250 ℃~270 ℃ in a salt bath furnace.The effect of super bainite on the mechanical properties of experimental steel was discussed by applying different tension-tension alternating loads with a fatigue-testing machine.The microstructural morphology of the sample was observed,and the phase composition of the sample was ascertained through SEM,TEM,and XRD analysis.A portion of the residual austenite in the microstructure was transformed into twin martensite through stress-induced transformation under loading.Tensile strength and ductility increased by nearly 32.4%.Results showed that austenite retained in the super bainite can improve steel toughness by generating stress-induced phase transformation.

关 键 词：超级贝氏体 残余奥氏体 应力诱发相变 疲劳载荷 强塑积 等温处理 贝氏体铁素体 化学势 

分 类 号：TG113[金属学及工艺—物理冶金]