Journal of Korea Foundry Society (한국주조공학회지)

Korea Foundry Society (한국주조공학회)
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Effects of Superheat and Coating Layer on Interfacial Heat Transfer Coefficient between Copper Mold and Aluminum Melt during Solidification

응고중 구리 주형과 알루미늄 용탕의 계면열전달계수에 미치는 용탕과열도와 도형재의 영향

  • Kim, Hee-Soo (New Materials Processing Team, Advanced Materials R&D Center, Korea institute of Industrial Technology) ;
  • Shin, Je-Sik (New Materials Processing Team, Advanced Materials R&D Center, Korea institute of Industrial Technology) ;
  • Lee, Sang-Mok (New Materials Processing Team, Advanced Materials R&D Center, Korea institute of Industrial Technology) ;
  • Moon, Byung-Moon (New Materials Processing Team, Advanced Materials R&D Center, Korea institute of Industrial Technology)
  • 김희수 (한국생산기술연구원 신소재개발본부 신소재공정팀) ;
  • 신제식 (한국생산기술연구원 신소재개발본부 신소재공정팀) ;
  • 이상목 (한국생산기술연구원 신소재개발본부 신소재공정팀) ;
  • 문병문 (한국생산기술연구원 신소재개발본부 신소재공정팀)
  • Published : 2004.10.20
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Abstract

The present study focused on the estimation of the interfacial heat transfer coefficient as a function of the surface temperature of the aluminum casting at the mold/casting interface to investigate the effects of superheat and coating layer. The casting experiments of aluminum into a cylindrical copper mold were systematically conducted to obtain the thermal history during solidification. The thermal history recorded by four thermocouples embedded both in the mold and the casting was used to solve the inverse heat conduction problem using Beck's method. The effects of superheat and coating on the interfacial heat transfer coefficient in the liquid state, during the solidification, and in the solid state were comparatively discussed. In the liquid state, the interfacial heat transfer coefficient is thought to be affected by the roughness of the mold, the wettability of the casting on the mold surface, and the thermophysical properties of the coating layer. When the solidification begins, the air gap forms between the casting and the mold, and the interfacial heat transfer coefficient becomes a function of the air gap as well as surface roughness and the superheat. In the solid phase, it depends only upon the thermal conductivity and the thickness of the air gap. The coating layer reduces seriously the interfacial heat transfer coefficient in the liquid state and during the solidification.

Keywords

References

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