不同应力状态下45钢断口形貌分析

Fracture topography analysis of C45 steel under different stress state

与传统的宏观断裂力学不同,细观损伤力学侧重于研究材料内细观损伤的演化对于材料宏观断裂的影响。该文以完全球化退火处理的45钢为对象,对设计的不同几何形状试件进行拉伸、压缩、扭转和精密冲裁试验,以获得不同应力三轴度条件下的断口形貌;通过数值模拟,并结合扫描电镜对不同应力状态下发生损伤和断裂的机理进行分析。

Comparing with the traditional macro-scale fracture mechanics, meso-scale mechanics focus on researching the effect of the inner damage evolution on the macro fracture of material. In this study, specimens of different geometry were designed with C45 steel, and used to perform tensile, compression, torsion and fine-blanking test as well, so as to obtain the fracture topogra phy under different stress triaxiality. With the aid of numerical simulation and SEM, the mechanism of damage and ductile frac rare in different stress state was investigated.