The Influence of Deep Rolling Process on Fatigue Durability for Vehicle Tie-Rod Component

Abstract

In the automotive industry, most of the components are consistently subjected to the dynamic loading due to the randomly observed situations from road inputs and periodic vibration from IC engine working during the operation. Such loadings cause the durability problem which may result in failure or cracking at stresses that are well below the yield strength of the material. Therefore, along with the development of new processing techniques, different surface treatment processes are applied to enhance the fatigue behavior of components. Being one of the mechanical surface treatment methods, deep rolling is an efficient way for improvement of fatigue performance by strengthening the critical section and providing compressive type of residual stresses. In this paper, the effect of the deep rolling process on fatigue behavior of steel stud in tie-rod used as steering system component was investigated. Force-Number of cycles curves (F-N graph) for the fatigue test have been obtained from the tests. Evaluation of the fatigue endurance limits of the stud at un-rolled condition and rolled conditions at three different loads were performed. Test data was analyzed with a regression line to account for the scatter using probability density functions. The results indicate a significant enhancement in the endurance limit following the implementation of the rolling process, as compared to the unrolled state. Furthermore, it was observed that the endurance limit proportionally increased in line with the rolling load. These findings underscore the crucial role of the deep rolling process in determining the optimal rolling load for the specific stud design and material conditions.