再结晶后面心立方金属的断裂模式及有限元分析

Fracture Mode of Recrystallized FCC Metals and FEM Analysis

为了研究再结晶对面心立方(FCC)金属断裂模式的影响,以纯铝为对象采用电子背散射衍射、拉伸试验和扫描电镜分析等研究了纯铝拉伸断裂的模式,并结合3D晶体有限元模拟了变形过程中纯铝中孔洞的长大行为。结果表明:由于晶粒间不均匀变形使得大角度晶界上的等效塑性应变大于单个晶粒中的等效塑性应变,孔洞易沿着大角度晶界长大,使得再结晶后FCC结构的纯铝易发生沿晶断裂。

To investigate the effect of recrystallization on failure model of FCC metals,the electron backscatter diffraction,tensile experiment and SEM were adopted to analyze the tensile fracture mode of pure aluminum,integrated with 3D crystal plasticity finite element method（FEM）,a unit cell was created to simulate the growth behavior of voids in pure aluminum during deformation.The results show that the equivalent plastic strain along the high-angle grain boundaries was larger than that in single crystals due to inhomogeneous deformation between the grains,and the void was easy to grow along the high-angle grain boundaries,and the fracture of the recrystallized pure aluminum with face-centered structure was intergranular fracture.