基于大范围应力三轴度的船用低碳钢断裂特性研究  

Fracture Properties of Ship-Build Mild Steel in Wide Range of Stress Triaxiality

作　　者：李营[1,2] 吴卫国[1] 朱海清[1] 杜志鹏[2] 张磊[2] 张玮[2] 

机构地区：[1]武汉理工大学交通学院,武汉430063 [2]海军装备研究院,北京100161

出　　处：《中国造船》2016年第3期54-64,共11页Shipbuilding of China

基　　金：国防基础研究项目(B1420133057);国家自然科学基金(11302259);非线性力学国家重点试验室开放基金(LNM201505);中央高校基本科研业务费专项资金(2014-yb-20)

摘　　要：基于有限元修正的平均应力三轴度值的方法,对缺口拉伸、纯剪切、压剪和单轴压缩等多种应力状态下的材料试样进行计算。应力三轴度从-0.33到1.33,涉及压缩、压剪、剪切、拉伸、多轴拉伸等多轴应力状态。最终拟合了两种计及应力三轴度损失的断裂准则,并通过Taylor杆撞击试验进行了仿真分析。结果表明:(1)舰用低碳钢的断裂应变与应力状态密切相关,且在不同的应力三轴度区间差异较大;(2)考虑应力三轴度影响的断裂准则能较好地预测船用低碳钢材料在复杂应力状态下的断裂行为。Triaxial state of stress has a significant effect on ductile fracture. In order to study dynamic damage properties of ship-build mild steel, experimental and numerical studies have been done in this paper. Modified method for calculating average stress triaxiality is proposed based on the finite element method. Micromechanics of fracture strain affected by stress triaxiality are analyzed; truncation effect of stress triaxiality is deduced. Furthermore, two types of fracture criterion are fitted to the measured data. The research results are verified through impact test of Taylor 5s bar.

关 键 词：多轴应力状态 船用钢 损伤特性 断裂准则 应力三轴度 

分 类 号：U661[交通运输工程—船舶及航道工程]