쇼트피닝한 스프링강의 피로균열진전 연구

A Study of Fatigue Crack Growth in Shot Peened Spring Steel

  • 박경동 (부경대학교 기계공학부) ;
  • 진영범 (부경대학교 기계공학부 대학원)
  • Park, Keyung-Dong (Department of Mechanical Engineering, Pukyoung National University) ;
  • Jin, Young-Beom (Department of Mechanical Engineering, Graduate School, Pukyoung National University)
  • 발행 : 2004.12.01

초록

Antifatigue failure technology take an important the part of current industries. Currently, the shot peening is used for removing the defect from the surface of steel and improving the fatigue strength on surface. Therefore in this paper the effect of compressive residual stress by shot peening on fatigue crack growth characteristics in stress ratio(R=0.1, 0.3, 0.6)was investigated with considering fracture mechanics. There is difference between shot peening specimen and unpeening specimen. Fatigue crack growth rate of shot peening specimen was lower than that of unpeening specimen. Fatigue lift shows more improvement in the shot peening material than in the unpeening material. And compressive residual stress of surface on the shot peening processed operate resistance force of fatigue crack propagation. That is the constrained force about plasticity deformation was strengthened by resultant stress, which resulted from plasticity deformation and compressive residual stress in the process of fatigue crack propagation.

키워드

참고문헌

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