Q235B钢材的微观断裂模型损伤系数识别

Damage coefficient identification of micromechanical fracture prediction models for steel Q235B

摘要:

为获取广泛应用的Q235B钢材的循环空穴增长 (CVGM) 和退化有效塑性应变 (DSPS) 微观断裂模型损伤系数，取材自热轧无缝钢管与冷弯高频焊管母材、热影响区和焊缝区，分别加工12个光滑和8个缺口试件进行低周往复加载材性试验，获取4种材料混合强化参数，利用Fortran语言编译了CVGM模型及DSPS模型程序代码，作为UVARM子程序嵌入ABAQUS中，识别了其CVGM和DSPS损伤退化系数，用于缺口圆棒试件实验过程模拟，取得较好预测效果.

Abstract:

In order to obtain the damage coefficient of Cyclic Void Growth Model (CVGM) and Degraded Significant Plastic Strain (DSPS) model for Steel Q235B widely used in China, taking four types of steel Q235B materials extracted from the hot-rolled seamless pipe and the matrix, heat affected zone as well as welded zone of cold-welding pipe respectively, twelve smooth specimens and eight notched specimens were machined. A series of low-frequency cyclic loading material tests were carried out to acquire the combined hardening parameters. The UVARM subroutines of CVGM model and DSPS model were developed in FORTRAN language and embedded in ABAQUS. The calibration of the damage degradation coefficients of CVGM model and DSPS model of four kinds of steel materials was performed. Based on the UVARM subroutine and identified damage coefficients, fracture initiation for the notched specimens can be predicted and simulation results match well with experimental results.