Experimental and numerical analysis of the life performance enhancement of rod ends used in automotive steering devices

Abstract

Rod ends used in automotive industry are the utmost important elements that play a critical role in suspension system and steering devices. They are exposed to high sudden forces in both axial and radial directions and so the life performance is one of the big challenge for the manufacturers. In this study, the effect of design parameters on increasing the fatigue life of rod ends was investigated. Existing rod ends were subjected to fatigue tests under +/- 40 kN, +/- 50 kN and +/- 70 kN loading. The analysis and test results showed that the fatigue life of the existing design was low and the damage generally started in areas with sharp corners or low radii. Thus, a new road end design was proposed and thanks to the optimized new design, the fatigue life of rod ends was increased from 135,310 cycles to 884,043 cycles on average under +/- 50 kN load. The obtained results show that the improvement of the sharp corners and radius of the road end enhance the fatigue performance significantly, which is very important for the manufacturers and designers in the automotive steering mechanisms.