中等厚度高强钢缺口板断裂试验及数值分析

Fracture test and numerical analysis of high strength notched steel plate with moderate thickness

为研究中等厚度高强钢断裂机理,对厚度为16 mm的Q345缺口板和开孔板各10个试件进行了拉伸断裂试验,研究了缺口尖锐度对中等厚度高强钢断裂模式的影响.试验表明,初始裂纹形成于缺口边缘内侧,缺口较尖锐的试件断裂延性较低,初始开裂点位于载荷位移曲线的强化阶段,呈脆性断裂;缺口较钝的试件断裂点位于载荷位移曲线的下降段,呈延性断裂.对高强钢缺口板和开孔板断裂试验进行了基于广义屈服模型和椭球面断裂模型的数值模拟和断裂分析,结果表明,金属椭球面断裂模型对预测中等厚度高强钢缺口板和开孔板的初始开裂有较高精度,但对中等厚度高强钢延性断裂的预测偏于保守.

In order to study the fracture mechanism of high strength steel plate with moderate thickness,the tensile fracture tests were performed for both 10 notched and 10 holed Q345 high strength steel plates with a thickness of 16 mm.The effect of notch sharpness(b/a) on the fracture mode of high strength steel plate was examined.The test results show that the initial crack initiates at the notch edge.The fracture ductility of the specimens with the sharper notch is lower,the initial cracking occurs in the hardeni...