차량의 스프링鋼에 압축잔류응력을 부여한 쇼트피닝 特性의 影響

The Shot-Peening Characteristic Effects of Compressive Residual Stress Induced Automotive Spring Steel

The purpose of this study is based on the effect of shot-peening upon life time characterization of corrosion fatigue crack progress of spring steel SAE 5155 that is commonly used for automotive purposes. Fatigue crack progress tests of ambient un-peening and shot-peening steel show the following results. Shot-peening process requires longer accumulation time of the compressive residual stress within materials and, therefore, higher corrosion resistance. The speed of fatigue crack progress, in general, is lower for the steel after shot-peening. This would be caused by the binding power of cracks from the stress residual stress during the progress of crack progress. Fatigue crack progress rate, in general, is lower for the steel after shot-peening comparing with un-peening processed one. This would be judged by the binding power of cracks from the compressive residual stress during the progress of crack progress.