EFfect of Molding Temperature and Debinding Conditions on Fabrication of Alumina Component by Injection Molding

금형온도와 탈지조건이 사출성형에 의한 알루미나 부품 제조에 미치는 영향

  • 임형택 (고려대학교 재료공학과) ;
  • 임대순 (고려대학교 재료공학과)
  • Published : 1995.05.01

Abstract

Alumina powder was coated with stearic acid and then mixed with isotactic polypropylene, atactic polypropylene as binders at 15$0^{\circ}C$ for 2 hours. The mixture was then injection molded at various mold temperatures using injection molding machine to investigate the effect of the molding temperature and debinding parameters on the formation of the defects. The molded specimens were debinded in both air and nitrogen atmospheres. Wicking and solvent methods were also used to enhance debinding efficiency. The specimens were prefired at 120$0^{\circ}C$ and then sintered at 150$0^{\circ}C$ for 3 hours. Various defects were formed at mold temoperature of 3$0^{\circ}C$, 6$0^{\circ}C$ and 10$0^{\circ}C$ and any noticeable defect was not formed at 85$^{\circ}C$. The density of green body increased with mold temperature. Debinding in air atmosphere was more effective than in nitrogen atmosphere. Results also proved that wicking and solvent treatments helped minimize the number of defects.

Keywords

Ceramic injection molding;Alumina;Debinding;Molding temperature;Defects

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