• 제목/요약/키워드: White etching layer(WEL)

검색결과 3건 처리시간 0.018초

White etching layer의 두께변화에 따른 접촉피로수명 평가 (Contact Fatigue Analysis of White Etching Layer according to Thickness Variation)

  • 서정원;권석진;전현규;이동형
    • 한국정밀공학회지
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    • 제27권8호
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    • pp.35-41
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    • 2010
  • White Etching Layer(WEL) is a phenomenon that occurs on the surface of rail due to wheel/rail interactions such as excessive braking and acceleration. Rolling Contact Fatigue(RCF) cracks on the surface of rail have been found to be associated with WEL. In this study, we have investigated RCF damages of white etching layer using twin disc testing and fatigue analysis. These tests consist of wheel flat tests and rolling contact fatigue tests. WEL has been simulated by wheel flat test. It has been founded that the WEL with a bright featureless contrast is formed on the surface of specimen by etching. Rolling contact fatigue test was conducted by using flat specimens with the WEL generated by the wheel flat test. It has been observed that two types of cracks occur within the specimen. The contact fatigue test was simulated in 2D elastic-plastic FE simulations. Based on loading cycles obtained from the finite element analysis, the fatigue life analysis according to the thickness variation of WEL was carried out. The longest fatigue life was observed from the thickness of 20um.