基于等效结构应力法的汽车后桥疲劳寿命分析

汽车支撑后桥是汽车底盘中主要的受力部件，承受着各个方向的载荷，其主要的损伤形式是在交变载荷作用下发生的疲劳失效。CAE仿真技术的广泛应用使得车身及零部件结构设计进入了一个崭新的阶段。本文首先利用三维软件CA-TIA建立某型支撑后桥的三维几何模型，并利用Hypermesh软件建立相应的有限元模型，根据工况设定相应的约束载荷，利用Ansys软件对后桥进行静力分析。之后将有限元分析结果导入Fe-safe软件，利用等效结构应力法分析了后桥在典型工况下的疲劳寿命。对比实际的疲劳冲击试验和CAE分析结果，预测结果与实验结果基本吻合，后桥产品的疲劳寿命满足质量要求。证明CAE疲劳仿真技术可以合理有效的预测寿命，有助于提高产品开发的质量和周期。

Fatigue Life Analysis of the Automobile Rear Axle Based on the Structure of Equivalent Stress Method

Rear axle is the main componment of automobile chassis, which under the load of each direction. The main damage form is fatigue failure under cyclic loading. CAE simulation technology has been widely used for automobile body and parts structure design and has entered into a new stage. In this paper,firstly the 3d geometric model of sub-compact driving axle housing was established by using 3d modeling software （CATIA） and finite element model based on Hypermesh software was established. The corresponding constraint load is set according to the working conditions and static analysis for rear axle is processed by Ansys software.Secondly,the fatigue life is analyzed under typical con-ditions by using Fe-safe. The driving axle fatigue life under typical conditions is analyzed by using the method of equivalent structure stress. Compared the actual impact fatigue test and CAE analysis results, the result show that the fatigue life of rear axle products meet quality requirements.The CAE simulation technology can be reasonable and effec-tive for prediction of fatigue life and the quality and the cycle of product development are improved.