PMMA材料断裂应力与银纹损伤研究

Maximum Drawing Stress Criterion

本文基于连续介质力学理论和最大拉应力准则 ,从能量的观点出发 ,根据能量守恒定律 ,提出了脆性材料的断裂应变能密度与断裂应变成线性关系 ,由此确定的平均应力为材料常数。并通过PMMA材料在不同应变率下的拉伸实验验证。同时通过表面银纹显微镜观察实验 ,研究了应变率对银纹密度的影响。

Based on the theory of continuum mechanics and maximum tensile stress criterion and conservation law of energy, this paper has proposed that fracture strain energy density of brittle materials is linear with their fracture strain, and that average stress decided by them is a material constant, which have been verified by PMMA materials tensile test at the different loading rates. At the same time, through the microscope test of surface, the effect on craze density by strain rate has been investigated as well.