| As the mainly load-bearing and force-transmitting component of the vehicle, the automotive drive axle housing burdens the weight of vehicle and transfers the force to the wheel. By the drive axle housing, the traction force, braking force and lateral force acted on the wheel are transferred to the suspension system, frame or carriage. According to the experience and the vibration theory, the crash of the axle housing is induced by the pulse of the road surface roughness and fatigue failure caused by alternating loads from the different hard work conditions.Because the driving condition of the vehicle is very complex, the strength and dynamic performance of the drive axle housing affect the operation safety of the vehicle. The reasonable design of the drive housing is one of the important ways to improve the ride comfort. Thus, it is necessary to analyze the strength, stiffness and dynamic performance of the drive axle housing.Based on the finite element method, the finite element analysis of dynamic performance and fatigue life prediction of the automotive drive axle housing is done by the FEM software ABAQUS and ANSYS Workbench in this paper. Firstly, the 3-D model of axle housing is established in CAD software Catia. Then, the model is meshed and analyzed by ABAQUS and ANSYS Workbench. The time-response characteristics of the stress and deformation and the effect of the damping coefficient and the friction coefficient on the carrying capacity of the drive axle housing are obtained by the time-history analysis of the sudden brake load case. Based on the modal analysis of the drive axle housing, the harmony analysis is done ,in which the natural frequency is evaluated and an improving suggestion is carried out. The fatigue analysis including the nonlinear interference fit contact evaluates the life and stress distribution when the interference fit is 0.01mm, 0.05mm and 0.1mm.The results of the finite element analysis show that the maximum Mises stress of the axle housing is less than the allowable stress value in the sudden brake load case. So the axle housing meets the strength requirement. The resonance frequency and amplitude-frequency curves of the dynamic stress are obtained in the harmony analysis, which can provide reference for the automotive drive axle housing design. The medium life of the drive axle housing is more than 800 thousand times and the least life is more than 500 thousand times when the interference fit is between 0.01mm and 0.05mm, which meets the requirement of the design standard. With the increasing of the interference fit, the region of the drive axle housing including interference fit becomes dangerous.According to the result of the finite element analysis, the changing-section design method is suggested in the drive axle housing design. To realize the reasonable use of the material, the daugerous region with large stress should be enhanced and the thickness of the safe region should be reduced. Meeting the requirement of the manufacture technology, the interference fit should be as little as possible, so as not to cause the significant decreasing of the life of the drive axle housing.
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