The solution of the crack-tip stress, strain fields for the power law type nonlinear viscoelastic materials, especially for the modified polypropylene, is obtained.
得到了幂率型非线性粘弹性材料，特别是改性聚丙稀的裂纹尖端应力、应变和位移场的解答。
2
Through analysis of result of rheology test, an appropriate viscoelastic constitutive model has been found to fit the curve of stress-strain.
通过对流变试验结果的分析，找到了一种比较好的粘弹性本构关系来拟合流变试验曲线。
3
Introducing the plastic strain the differential constitutive equation for viscoelastic and plastic materials is deduced from multi-integral constitutive equation for nonlinear viscoelastic materials.