汽车车身TRIP700钢的疲劳特性分析  

Analysis on Fatigue Characteristics of Automobile Body TRIP700 Steel

作　　者：高云[1] 吉武俊[1] 

机构地区：[1]河南职业技术学院,河南郑州450046

出　　处：《热加工工艺》2015年第4期216-218,222,共4页Hot Working Technology

基　　金：河南省软科学研究计划项目资助(132400410039)

摘　　要：采用不同的退火工艺对汽车车身用TRIP700钢进行热处理,然后对0.9 mm厚的TRIP700钢进行疲劳测试,并对热处理后的TRIP700钢进行显微组织分析和拉伸测试。实验结果表明:分级退火处理的TRIP700钢的残余奥氏体含量较低,具有较高的屈服应力和较低的应变硬化率;利用对数非线性拟合方程得到在应力比为0.1,加载频率为20 Hz的TRIP700钢高周疲劳S-N曲线,均匀化退火与分级退火的TRIP700钢的疲劳极限值分别是472 MPa和486 MPa。Different annealing processes were used to heat treat at TRIP700 steel used for automobile body, then the fatigue testing was carried out for 0.9 mm thick TRIP700 steel, and after heat treatment, the microstructure analysis and tensile testing of TRIP700 steel were carried out. The results show that the content of retained austenite of TRIP700 steel after classification annealing is low, which has low yield stress and high strain hardening rate. The nonlinear fitting equations are used to fit the fatigue data to obtain S-N fatigue curve of TRIP700 steel in high-cycle regime under conditions of the stress ratio of 0.1 and the loading frequency of 20 Hz, and the fatigue limits of TRIP700 steel via the homogenization annealing and grading are 472 MPa and 486 MPa, respectively.

关 键 词：TRIP700钢 疲劳特性 残余奥氏体 非线性拟合 拉伸测试 

分 类 号：TG156.4[金属学及工艺—热处理]