The Fatigue Behavior and Life Analysis of Carbornitrizing SCM415 Steel under Two Level Block Loading

이단응력에서 침탄질화처리재의 피로거동 및 수명 해석

Under two level block loading, the carbornitrizing specimen can be expected to show different behavior from other uniform material because the properties of surface layer and inner material are different from each other. In this research, the modified Marco-Starkey cumulative theory, which considers load interaction effect, can predict the life of SCM415 carbornitrizing and original notched and smooth specimen, In the low-high test of carbornitrizing specimen which has long life, however, we may additionally consider the increase of life by means of the stress hardening of inner original material.