基于临界面法的高强度铸造铝合金微动疲劳特性研究

Research on Fretting Fatigue Properties of High Strength Cast Aluminum Alloy Based on Critical Plane Method

用ANSYS对高强度铸造铝合金的微动疲劳特性进行仿真模拟,得到接触面上的应力、应变分布规律;基于SWT临界面法预测微动裂纹的萌生位置,用实验值拟合得到微动疲劳寿命预测参数并用临界面法预测微动疲劳寿命。结果表明:在法向夹紧力不变时,微动疲劳寿命会随着轴向力的增大而减小,且轴向力存在一个临界值,超过这个临界值,构件寿命会急剧下降。在HYS-100型微动疲劳试验机上对高强度铸造铝合金的微动裂纹萌生位置及寿命进行实验验证。结果表明,SWT临界面法预测裂纹萌生位置与试件实际断裂位置一致,预测寿命与实际寿命在误差允许范围内。

The fretting fatigue properties of high strength cast Aluminum alloy were simulated by ANSYS, and the stressand strain distribution on the contact surface was got.The crack initiation location was predicted based on the SWT criticalsurface method,the fretting fatigue life prediction parameters were fitted by the experimental values, and the fretting fa.tigue life was predicted by the critical surface method.The results show that, with the increasing of the axial force, the fret.ting fatigue life is decreased under the constant clamping force.There is a critical value of axial force, once beyond thiscritical value, the life of the high strength cast Aluminum alloy component will decrease sharply.The fretting crack initia.tion location and lifetime of high strength cast Aluminum alloy were experimentally verified on the HYS.100 fretting fatiguetesting machine.The results show that the predicted results are in agreement with the experimental results, the predictedlife and the actual life span are within the limits of the error.