최대응력을 이용한 상용차 Leaf spring 의 피로강도 평가

Suspension system of vehicle is very important part because it acts on ride comport and safety. And the spring is one of major part vehicle. Therefore it has to be designed to operate under severe conditions to ensure enough endurance. In general, the most typical and traditional method for fatigue design methods need many additional fatigue tests according to its geometry, materials, and fatigue loading condition. This indicates that a lot of cost and time for it have to be consumed. In this paper. the ΔP-N_f curve were obtained by fatigue tests. Using these results, ΔP-N_f curves were rearranged in to the Δδ_f relation with the maximum stress. By using the maximum stress and the fatigue data previously obtained as the fatigue test results, the fatigue design criterion could be predicted without any additional fatigue tests.