Effect of Cast Microstructure on Fatigue Behaviors of A356 Aluminum Alloy for Automotive Wheel

자동차휠용 A356 알루미늄 합금의 주조조직이 피로특성에 미치는 영향

  • 송전영 (부경대학교 신소재공학부) ;
  • 박중철 (포항산업과학연구원 분석평가본부) ;
  • 안용식 (부경대학교 신소재공학부)
  • Received : 2010.01.12
  • Accepted : 2010.01.25
  • Published : 2010.02.26

Abstract

Recently, automotive industry is attempting to replace steels for automotive parts with light-weight alloys such as aluminum alloy, because of the growing environmental regulations governing exhaust gas and the engine effectiveness of a vehicle. The low cycle fatigue (LCF) and high cycle fatigue (HCF) properties as well as the microstructure and tensile property were investigated on the low pressure cast A356 aluminum alloy wheel, which was followed by T6 heat treatment. The cast microstructure of the alloy influenced significantly on the low cycle and high cycle fatigue behaviors. The rim part of cast aluminum alloy wheel showed higher low cycle and high cycle fatigue strength compared with the spoke part, which should be caused by higher cooling rate of rim part. The spoke part of the wheel showed coarser dendrite arm spacing (DAS) and wide eutectic zone in the microstructure, which resulted in the partial brittle fracture and lower fatigue life time.

Keywords

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