Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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A Study on Durability Characteristics of Automobile Clutch Diaphragm Spring Steel According to Heat-Treatment Condition

자동차 클러치용 다이아프램 스프링 강(50CrV4)의 열처리 조건에 따른 내구특성에 관한 연구

  • 남욱희 (평화 발레오(주)연구개발부) ;
  • 이춘열 (영남대학교 기계공학) ;
  • 채영석 (영남대학교 기계공학) ;
  • 권재도 (영남대학교 기계공학) ;
  • 배용탁 (영남대학교 대학원 기계공학) ;
  • 우승완 (영남대학교 대학원 기계공학부)
  • Published : 2000.02.01
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Abstract

An automobile clutch diaphragm spring is operating in a closed clutch housing under high temperature and subject to high stress concentration in driving condition, which frequently causes cracks and fracture. The material of spring is required to possess sufficient fatigue strength and tenacity, which depend largely on the condition of tempering heat treatment. In this paper, specimens are made under a number of different tempering temperatures md tested to find the optimal tempering heat treatment condition. The experiments include the verification of microscopic structure, hardness, tensile strength, fatigue crack growth rate, stress intensity factor range and residual stress. Also, decarbonization, which occurs in actual heat treatment process, is measured and allowable decarbonization depth is studied by durability test.

Keywords

References

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