자동차 현가장치재의 부식피로수명에 따른 압축잔류응력의 영향

The Effect of Compressive Residual Stress according to Corrosion Fatigue Life of Automobile Suspension Material

  • 기우태 (부경대학교 대학원 기계공학부) ;
  • 박성모 (부경대학교 대학원 컴퓨터공학과) ;
  • 문광석 (부경대학교 전자공학부) ;
  • 박경동 (부경대학교 기계공학부)
  • Ki, Woo-Tae (Department of Mechanical Engineering, Pukyoung National University) ;
  • Park, Sung-Mo (Department of Computer Engineering, Pukyoung National University) ;
  • Moon, Kwang-Seok (Department of Electronics Engineering, Pukyoung National University) ;
  • Park, Kyeong-Dong (Department of Mechanical Engineering, Pukyoung National University)
  • 발행 : 2008.09.01

초록

A study of new materials that are light-weight, high in strength has become vital to the machinery of auto industries. But then, there are a lot of problems with developing such materials that require expensive tools, and a great deal of time and effort. Therefore, the improvement of fatigue strength and fatigue life are mainly focused on by adopting residual stress. And Influence of corrosive condition for corrosion fatigue crack was investigated, after immersing in 3.5%NaCl, $10%HNO_3$+3.5%HF, $6%FeCl_3$. The immersion period was performed for 365days. The compressive residual stress was imposed on the surface according to each shot velocity based on shot peening, which is the method of improving fatigue life and strength. Fatigue life shows more improvement in the shot peened material than in the un peened material in corrosion conditions. The threshold stress intensity factor range was decreased in corrosion environments over ambient. Compressive residual stress of surface on the Shot-peen processed operate resistance force of fatigue crack propagation. The fatigue crack growth rate of the Shot-peened material was lower than that of the un peened material. Also m, fatigue crack growth exponent and number of cycle of the shot peened material was higher than that of the un peened material. That is concluded from effect of da/dN.

키워드

참고문헌

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