A criterion for ductile rupture is derived using Rice’s theory for macroscopic strain localization, and a constitutive relation for porous plastic solids that accounts for inhomogeneous yielding at the mesoscale. At the microscopic scale, it is assumed that failure occurs by void coalescence along a band of voids. An approximate, parameter-free closed form expression for the failure criterion is derived as a function of a single scalar damage variable –the porosity– and the macroscopic stress state, characterized by the stress triaxiality and Lode parameters. For practical applications, an uncoupled approach is developed whereby the failure criterion is supplemented with a damage-free plasticity model and a loading path dependent damage evolution law. The predictive capabilities of the approach are illustrated by comparisons with finite element cell model studies. In particular, the influence of strain hardening is investigated in some detail.

延性断裂的判据是根据莱斯的宏观应变局部化理论推导的，而多孔塑性固体的本构关系则在中尺度上造成了不均匀屈服。在微观尺度上，假设失效是由于沿着空隙带的空隙合并而发生的。根据单个标量损伤变量（孔隙率）和宏观应力状态（以应力三轴性和Lode参数为特征），导出了失效准则的近似，无参数的闭合形式表达式。对于实际应用，开发了一种非耦合方法，其中通过使用无损伤可塑性模型和依赖于载荷路径的损伤演化规律来补充失效准则。通过与有限元单元模型研究的比较说明了该方法的预测能力。特别是，详细研究了应变硬化的影响。