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采用虚功率增率有限元法及Ｊ２形变理论，模拟韧性金属平面应变颈缩扩展、剪切断裂演化过程。运用载荷控制卸载的自动识别方法以及各增量步间Ｅｕｌｅｒ控制方法，实现了均匀变形与非均匀变形临界状态的稳定过渡。采用本构方程的Ｅｕｌｅｒ显式积分，对Ｊ２形变理论塑性加载与弹性卸载的不连续性进行了改进，保证了变形局部化模拟过程的可靠性。最后，讨论了不同硬化指数及初始几何不均匀性对局部化力学行为的影响。
Adopting virtual finite element method and J2 deformation theory, the plane strain of ductile metal is expanded and the evolution of shear fracture is simulated. The automatic identification method of load control unloading and the Euler control method of each increment step are adopted to realize the stable transition between the uniform deformation and the non-uniform deformation critical state. By using Euler explicit integral of constitutive equation, the discontinuities of plastic deformation and elastic unloading of J2 deformation theory are improved, which ensures the reliability of the deformation localization simulation process. Finally, the effects of different hardening indices and initial geometric inhomogeneities on the local mechanics behavior are discussed.