차량용 스프링강의 피로균열진전에 미치는 압축잔류응력의 영향

The Effect of Compressive Residual Stress on The Fatigue life in Spring Steel for vehicles

  • 박경동 (부경대학교 기계공학부) ;
  • 하경준 (부경대학교 기계공학부) ;
  • 박형동 (부경대학교 기계공학부)
  • 발행 : 2003.01.01

초록

Nowadays, many components used in machinery industry is required lightness and high strength. The shot-peening method is used in order to improve the fatigue life of spring steel(JIS G SUP-9) which is used in suspension of automobile. The compressive residual is induced in this shot-peening process. This paper investigated the effect of the residual compressive stress on the fatigue crack growth characteristics. Main results are summarized as follows. 1. The fatigue crack growth rate on stage II is conspicuous with the level of compressive residual stress and is dependent on Paris equation. 2. Although the maximum compressive residual stress is deeply and widely formed from surface, it does not improve the fatigue life comparing when maximum compressive residual stress is formed in surface. 3. The threshold stress intensity factor range is increased with increasing compressive residual stress. 4. In fracture surface of fatigue crack growth it is investigated that compressive residual stress remarkably retards fatigue crack growth.

키워드

참고문헌

  1. 破壞力學 入門 村上;大南
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