基于寿命预测模型的微动疲劳影响因素

Research on Influencing Factors of Fretting Fatigue Based on Life Prediction Model

摘要:

以ABAQUS有限元分析软件为工具,通过计算接触面上的接触应力p(x)及切向应力τ分布,求得了Ruiz微动损伤参数k2(x),并以此为基础,建立了一种微动疲劳寿命预测模型,经验证该模型预测值与实验值比较吻合,证明了该模型的合理、有效性。利用所得模型,研究了3种参数变化对微动疲劳寿命的影响,结果表明:在其他参数保持不变的情况下,随着接触压力的增加,微动疲劳寿命迅速下降,在达到一个最低值后,随着压力的增加寿命反而增加；微动疲劳寿命随轴向应力增加而下降；对于较低的接触压力,寿命随压头半径的增加而增加,但在较高的接触压力下,随着压头半径的变化寿命几乎保持不变。

Abstract:

The distributing of contact pressure and tangential stress were calculated based on finite element software/ABAQUS. With them the Ruiz fretting damage parameter was obtained, based on which a new model for predicting fretting fatigue life was presented, and then the rationality and effectiveness of the model were validated according to the contrast of experiment life and predicting life. At last influence of three parameters on fretting fatigue life was investigated with the model. The results showed that life decreased quickly with increasing of contact pressure, and then increased on the contrary, but it always decreased with increasing of axial stress. In lower contact pressure the fretting fatigue life increased with increasing of pad radius, but it almost did not change in the higher values.