【摘要】 针对含孔洞镁合金材料的宏观力学性能、变形破坏机理,采用多尺度方法建立了准确的镁合金体胞有限元模型,并利用所发展的多尺度本构模型,结合有限元方法获得了在宏观拉伸载荷下材料的局部和宏观特性。多尺度方法分析细观单元体的变形结果表明,随着宏观载荷的增加,宏观上显示出的差异非常微小,但是在细观单元体的变形过程中明显观察到,随着载荷步的增加,含长方体形孔洞的塑性变形能力逐渐递减,且应力集中现象比含圆柱形孔洞的细观模型明显。更多还原

【Abstract】 In order to investigate the macroscopical mechanical performance of magnesium alloy material containing pore and the mechanism during distorting destructing,an accurate finite element model of magnesium alloy using the multi-scales method was developed,and the macroscopic properties of material under the macroscopic tensile load using the developed constitutive model of multi-scales and finite element method was obtained.By analyzing the distortion results of meso-model through the multi-scales method,with macroscopical load increasing,the difference demonstrated on the macroscopic is very small,however,with the increase of the load step,the phenomenon that the ability of plasticity deformation of the meso-models which includes the cuboid pore decreased gradually remarkable and the phenomenon of stress centralized is more severity than the meso-models including cylindrical pore could be obviously observed during the process of deformation on the meso-models.更多还原