非线性疲劳损伤累积理论研究

为解决两级载荷作用下的材料常在损伤值不为一时破坏的问题，在原有常用疲劳累积理论的基础上，避开等效损伤，并考虑加载顺序、领域潜在损伤和损伤的非线性对材料疲劳寿命的影响，建立了一种非线性疲劳损伤累积模型及其计算公式，并利用两种材料疲劳实验数据，通过该模型预测了它们疲劳寿命，所得结果符合实际，证明了该模型及其计算公式对材料进行寿命预测是可行的．

Unlinear fatigue damage cumulative theory

In order to resolve the problem that the damage value under two level loads isn' t equal to one, a cumulative nonlinear damage model and its math formula for fatigue are put forward by using the usual cumulative damage theories, avoiding the equivalent damage and considering the effect on material for load sequence, domanial latent damage and damage' s uneven character. The fatigue life values under the model are calculated from the two kinds materials' experiment data. The calculated data accord with the fact and indicate that life forecast by the model and its math formula are practical.