冷轧压下率对高氮奥氏体不锈钢组织性能的影响  

Effect of cold rolling reduction rate on microstructure and property of high nitrogen austenitic stainless steel

作　　者：张宇飞 刘海涛[1] 郑淮北 ZHANG Yufei;LIU Haitao;ZHENG Huaibei(State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China;Chengdu Advanced Metal Materials Industrial Technolgy Research Institute Co.,Ltd.,Chengdu 610300,China)

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819 [2]成都先进金属材料产业技术研究院股份有限公司,四川成都610300

出　　处：《轧钢》2022年第6期159-164,182,共7页Steel Rolling

摘　　要：针对当前对高氮奥氏体不锈钢冷变形过程中的微观组织演变、强化机理有待进一步研究的现状,对高氮奥氏体不锈钢进行压下率为5%~70%的冷轧及拉伸实验,利用OM、SEM及TEM观察并分析微观组织,研究了高氮奥氏体不锈钢冷变形过程中微观组织演变及力学性能的变化规律。结果表明:冷轧压下率增加到15%时,位错从单滑移变为多滑移和交滑移;冷轧压下率增加到30%时,出现形变孪晶;冷轧压下率增加到50%时,出现马氏体相变。当冷轧压下率由5%增加至70%时,钢板的屈服强度由529.9 MPa增加至1 499.8 MPa,抗拉强度由917.0 MPa增加至1 698.6 MPa,伸长率由71.3%降低至12.2%。利用Ludwigson模型拟合了冷轧钢板的真应力-真应变曲线,发现随冷轧压下率的增加,实验钢的应变硬化指数降低,均匀变形能力减弱。In view of the present situation that the evolution of microstructure and the strengthening mechanism of high nitrogen austenitic stainless steel during cold deformation need further study, the cold rolling with 5%-70% reduction rate and tensile tests were carried out on high nitrogen austenitic stainless steel. The microstructure was observed and analyzed by OM, SEM and TEM. The microstructure evolution and mechanical properties of high nitrogen austenitic stainless steel during cold deformation were studied, and the conclusion was drawn that when cold rolling reduction rate increased to 15%, the dislocations began to change from single slip to multiple slip and cross slip. When cold rolling reduction rate increased to 30%, deformation twins began to appear. When cold rolling reduction rate increased to 50%, martensitic transformation began to appear. When cold rolling reduction rate increased from 5% to 70%, the yield strength of the sheet increased from 529.9 MPa to 1 499.8 MPa, the tensile strength increased from 917.0 MPa to 1 698.6 MPa, and the elongation decreased from 71.3% to 12.2%. The Ludwigson model was used to fit the true stress-true strain curve of cold rolled sheet. It was found that with the increase of cold rolling reduction rate, the strain hardening exponent of experimental steel decreased and the uniform deformation ability decreased.

关 键 词：高氮奥氏体不锈钢 冷轧压下率 微观组织 力学性能 加工硬化 

分 类 号：TG142.71[一般工业技术—材料科学与工程] TG335.12[金属学及工艺—金属材料]