韧性金属大变形拟流动角点理论及应用*
Quasi-Flow Corner Theory on Large Plastic Deformation of Ductile Metals and its Applications
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摘要: 本文提出韧性金属弹塑性大变形拟流动角点理论(quasi-flow corner theory).该理论从塑性变形正交法则出发,将“模量衰减函数”及屈服面的尖点效应引入本构模型,从而实现了由正交法则本构模型向非正交法则本构模型以及从塑性加载向物理弹性却载的光滑过渡,使一般无角点各向异性硬化屈服函数与有角点硬化情形相结合成为可能。用于数值模拟各向异性金属薄板单向拉伸失稳与剪切带分析并与实验结果作比较,表明本文理论的有效性。Abstract: A quasi-flow corner theory on lalge plastic deformation if ductile metals is proposed in this paper. From orthogonal rule of plastic flow, the theory introduces a "modulus rethtced function" and a corner effect of yield surface into the constilulive model of elastic-plastic large deformation. Thereby, the smooth and continuous transitions from orthogonal constitutive model to non-orthogonal one, and from plastic loading to elastic unloading are realized. In addition, the theory makes it possible to connect general anisotropic yield functions with corner hardening effect. The comparison between numerical simulation and experimental observation for the uniaxial tensile instability and shear band deformation of anisotropic sheet metals shows the validity of the present quasi-flow corner theory.
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Key words:
- quasi-flow corner theory /
- modulus reduced function /
- shear band /
- Anisotropy
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