基于累积损伤理论的ST12钢T型点焊件寿命研究  

Life Study on T-type Spot Welded Specimen of ST12 Steel Based on Cumulative Damage Theory

作　　者：侯晓丹[1] 王瑞杰[1] 雷星海 HOU Xiaodan; WANG Ruijie; LEI Xinghai(Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming 650500, China)

机构地区：[1]昆明理工大学机电工程学院

出　　处：《热加工工艺》2018年第19期196-201,共6页Hot Working Technology

基　　金：国家自然科学基金资助项目(51065012)

摘　　要：对低碳钢T型撕裂拉伸点焊试件分别进行低-高和高-低两级加载疲劳试验,并利用线性和非线性疲劳累积损伤理论进行寿命预测。对于低-高加载,非线性预测结果较线性稍好一些;对于高-低加载,由于高载下的＂过载效应＂,线性预测结果与非线性预测结果都不太理想。针对高-低加载下的寿命预测误差,本文提出一种基于CHABOCHE修正模型的非线性疲劳累积损伤模型,分别考虑了两级应力幅以及疲劳塑性指数的影响。通过对比后发现,修正后的模型预测点焊寿命能力较原模型有所改善。The low-high and high-low loading fatigue tests of the mild steel T-type tear tensile spot welding specimens were carried out respectively, and the life was predicted by using the linear and nonlinear fatigue cumulative damage theory.For low-high loading, the results of nonlinear prediction are better than that of linear prediction. For high-low loading, the linear and non-linear predicted results are all not good due to the overload effect at high load. Aiming at the life prediction error under high-low loading, a nonlinear fatigue cumulative damage model based on CHABOCHE revised model was proposed in this paper. The effects of two-level stress amplitude and fatigue plasticity index were considered. After comparison, it is found that the predictive ability of the revised model is better than that of the original model.

关 键 词：T型撕裂拉伸 点焊 非线性累积损伤 疲劳寿命预测 

分 类 号：TG407[金属学及工艺—焊接] TG405