延性损伤的能量模型

AN ENERGY MODEL OF DUCTILE DAMAGE

采用材料在受力变形过程中耗散的塑性应变能定义材料的延性损伤变量,可以克服现有延性损伤变量定义的局限,完整描述材料在廷性损伤全过程中的损伤变化情况;实测方便,精度易于保证;还建立了相应的损伤演化方程和损伤材料的应力-应变本构方程,由其获得的损伤准则等价于第四强度理论。

In this paper, the plastic strain energy that a material absorbs in static loading is used to define the ductile damage variable of the material, which could overcome the limitations of the other definitions and describe all damage changes in the ductile damaging process. The damage variable can be measured easily and accurately under practical conditions. In accordance with the energy definition, the damage evolution equation and the constitutive equation of the damaged material are established, which are identical with the experimental data of a low carbon steel. The damage criterion to which this approach leads is equivalent to the fourth strength theory of material mechanics.