一种改进的当量应变能密度方法

A modified equivalent strain energy density method

讨论了循环加载下材料的塑性应变能、储能和热能耗散,发现当量应变能密度(equivalent strain energy density,ESED)准则相比Neuber准则多考虑了塑性应变能密度,因此当量应变能密度准则局部应变场估计值会远低于Neuber准则的估计值.提出改进的当量应变能密度方法,改进方法的估算值比Neuber准则更接近试验值,且寿命估计结果在工程上应用安全.改进的当量应变能密度准则的估计结果与疲劳失效试验结果符合较好.

Plastic strain energy density,stored energy and energy dissipation were discussed in the case of cyclic loading.Be-cause plastic strain density was taken into account by the ESED method,the Neuber rule normally overestimates the local strains while the ESED method underestimates the local strain.The result of the modified ESED method is closer to test results and the estimated life is safe for engineering application.The results predicted by the modified ESED rule are in correspondence with those of fatigue experiments.