Investigation into the Effects of Shot Peening on the Fretting Fatigue Behaviour of 65Si7 Spring Steel Leaf Springs

摘要

Leaf springs are subjected to varying stresses and vibrations due to road conditions. The influence of high contact pressures and temperatures follow fretting fatigue between two mating leaf surfaces. The work presented in this paper relates to improvement in fatigue and fretting fatigue performance of leaf springs using shot peening and coatings. The fatigue life of 65Si7 spring steel leaf springs has been determined experimentally at various shot peening conditions and optimum shot peening intensity is found. Full-scale leaf spring laboratory testing and specimen testing were carried out to show the extent of improvement in fatigue life as a result of shot peening. Structural damping is found to be an important surface characteristic of shot peened surfaces for reducing fretting fatigue. The effects of shot peening conditions and damping factor for minimizing fretting fatigue failures are discussed.