摘要
本文采用一种弹性/粘塑性模型,对扩展裂纹尖端应力应变场进行了渐近分析。文中假定,弹性阶段的粘性效应可以略去,仅在塑性应变中粘性才起作用。对这种模型,文中导出了一种率敏感型的本构关系。并进一步导出了裂纹尖端应力应变场的动力学方程。通过量级分析,给出了尖端场的应力应变奇异性指数。并且讨论了弹性,塑性及粘性三者的匹配条件。对Ⅲ型裂纹进行了具体的分析计算。对各个不同参数的选取进行了详细的分析,讨论了解的性质随各参数的变化规律。
The asymptotic analysis of he stress and strain field at a propagating crack tip is given by means of an elastic-viscoplastic model. It is assumed that the viscosity effect can be neglected for elasticity strain, and only for plasticity strain, the viscosity is significant. By use of this model, the constitutive relations of a rate sensitive material and the dynamic equations of the stress and strain field a crack-tip are derived. The stress and strain singularity exponent of crack-tip field is given by means of the asymptotic analysis. The matching condition among elastisity, plastisity and viscosity is discussed. For anti-plane shear crack the detailed analysis is given. The numerical calcula tions are carried out for various parameters of materials. The feature of the numerical solutions is discussed in detail.
出处
《力学学报》
EI
CSCD
北大核心
1993年第2期159-168,共10页
Chinese Journal of Theoretical and Applied Mechanics
关键词
裂纹
尖端
裂纹扩展
弹塑性材料
elastic-viscoplastic material, viscosity coefficient, Mach number, singularity exponent
