A study of interface heat transfer coefficient between die and workpiece for hot forging

열간단조시 금형과 소재간 계면열전달계수에 관한 연구

  • 권진욱 (한국기계연구원 소성응용그룹) ;
  • 이영선 (한국기계연구원 소성응용그룹) ;
  • 권용남 (한국기계연구원 소성응용그룹) ;
  • 이정환 (한국기계연구원 소성응용그룹) ;
  • 배원병 (부산대학교 정밀기계공학과)
  • Published : 2004.05.01

Abstract

The temperature difference between die and workpiece has been frequently caused to various surface defects. The distribution and change fur the temperature of forged part should be analyzed to prevent the generation of various defects related with the temperature. The surface temperature changes were affected with the interface heat transfer coefficient. Therefore, the coefficient is necessary to predict the temperature changes of die and workpiece. In this study, the experimental and FE analysis were performed to evaluate the coefficient with a function of pressure, temperature, material, and etc. The sealed die upsetting was used to measure the coefficient on pressure over the flow stress. AISI1045, Al6XXX, and Pure-Cupper were used to analyze effects according to the material. The coefficient was increased with step-up of pressure between die and workpiece. And, Al6XXX was larger than the AISI1045 and Pure-Cupper up to the five times.

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