一、引言韧性断裂是金属材料破坏的主要形式之一。实验观察和研究表明。金属材料的韧断是宏观塑性变形导致的断裂。细观上多数情况下是材料内部空穴形核、扩展和聚合的结果。Hancock和Mackenzie将理想化空穴扩展馍型——R—T模型推广应用到硬化材料断裂阶段,绐出ε_F=ε_d+α_1 exp(- 3/2 σ_m/σ_e) (1)式中,ε_F:断裂应变;ε_d:形核应变;σ_m:平均应力;σ_e:Mises等效应力;α_1:常数。 (1)式和宏观唯象研究结果[5,7] ε_F=F (R。) (2)相一致。(R。=σ_m/σ_e——三轴应力状态表 I. INTRODUCTION Ductile fracture is one of the main forms of metal material destruction. Experimental observation and research show. Rupture of the metal material is caused by macro-plastic deformation of the fracture. In most cases, microscopic results are nucleation, expansion and polymerization of holes inside the material. Hancock and Mackenzie extended the ideal cavity expansion type-R-T model to the fracture stage of the hardenable material, and found out ε_F = ε_d + α_1 exp (- 3/2 σ_m / σ_e) (1) where ε_F: Fracture strain; ε_d: nucleation strain; σ_m: average stress; σ_e: Mises equivalent stress; α_1: constant. (1) and macroscopic phenomenology research results [5,7] ε_F = F (R.) (2) are consistent. (R. = σ_m / σ_e - triaxial stress state table