An Investigation of Surface Appearance of an Injection-Molded Plastic Part with Various Induction Heating Conditions

고주파 가열조건에 따른 플라스틱 사출성형품의 표면특성 고찰

  • Sohn, Dong-Hwi (School of Mechanical Design and Automation Engineering, Seoul National University of Technology) ;
  • Seo, Young-Soo (School of Mechanical Design and Automation Engineering, Seoul National University of Technology) ;
  • Park, Keun (School of Mechanical Design and Automation Engineering, Seoul National University of Technology) ;
  • Lee, Kwang-Woo (Mobase Co., Ltd.)
  • 손동휘 (서울산업대학교 기계설계자동화공학부) ;
  • 서영수 (서울산업대학교 기계설계자동화공학부) ;
  • 박근 (서울산업대학교 기계설계자동화공학부) ;
  • 이광우 ((주)모베이스)
  • Published : 2009.12.31

Abstract

High-frequency induction is an efficient way to rapidly heat mold surface by electromagnetic induction. In the present work, high-frequency induction heating is applied to injection molding of a mobile phone cover in order to eliminate weldlines by efficiently raising the mold temperature. Through the induction heating experiments, the maximum temperature of $143^{\circ}C$ is obtained on the mold surface in 3s of heating, which is higher than the glass transition temperature of the resin material. An injection molding experiment is then performed with the aid of induction heating, from which we can successfully remove all the weldlines of the mobile phone cover. The effect of induction heating conditions such as the heating power and the heating time on the surface appearance is experimentally investigated.

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