쇼트피닝가공한 평기어의 최적 피닝강도 탐색에 관한 연구

A Study on the Investigation of Optimal Peening Intensity for Shot Peened Spur Gear

The shot peening process is often used to improve fatigue properties of metal parts. Among them, It is the most use in an auto-component. In order to achieve optimum, repeatable and reliable fatigue enhancement from the shot peening process, the important shot peening parameters must be controlled. In this paper, the optimum peening intensity (Almen intensity) condition is investigated by experiment. The Spur Gear steel was used to investigate shot peening effects. The fatigue life at $\sigma_a=1,050$ and $\sigma_a=1,250MPa$ first gently increases, then drops gently as peening intensity increases compared with unpeened specimen. Experimental results show that the optimum peening intensity range is $0.391\~0.434mmA$..So the fatigue strength and fatigue life have been tremendously increased by optimum-peening treatment. However, the fatigue strength and fatigue life have been decreased by over peeing.