TC4钛合金GTN损伤模型反向标定法研究

通过拉伸试验得到TC4钛合金载荷-位移曲线,研究反向标定法确定GTN孔洞损伤模型参数。通过有限元模拟,研究GTN模型6个待定参数对模拟结果的影响。结果表明,参数f0和fN需要通过反向标定法确定,εn可由拉伸试验确定,Sn可通过计算确定,fc和fF可由模拟结果直接给出;TC4钛合金的孔洞损伤随颈缩过程的产生迅速发展,直至断裂。

Study on GTN Damage Model of TC4 Titanium Alloy by An Inverse Approach

According to uniaxial loading-displacement curves of TC4 titanium alloy,The parameters of Gurson-Tvergaard-Needleman model(GTN model) were determined by an inverse approach.The influence of 6 different GTN model parameters on simulation results were studied by finite element method.It is found that only the parameters of f0 and fN need to be determined by the inverse approach,εn defined by tensile test,Sn determined by calculation,fc and fF could be given by simulation results directly.Voids damage evolution becomes faster with appearing of necking stages of TC4 titanium alloy,until failure fracture.