A Study on the Gravity Segregation in Monotectic Al Alloys.(II);The Effect of Master Alloy Addition on the Distribution of Pb, Bi Particles

Al계 편정합금의 중력 편석에 관한 연구(II);Pb, Bi 입자의 분산에 미치는 모하금 첨가의 영향

  • 황호을 (삼선공업(주) 기술연구소) ;
  • 이재하 (전북대학교 금속공학과) ;
  • 김희명 (한양대학교 재료공학과) ;
  • 최정철 (아주대학교 재료공학과) ;
  • 윤의박 (한양대학교 재료공학과)
  • Published : 1990.10.20

Abstract

To improve free-cutting property, fine Pb, Bi particles is necessary to be distributed evenly in Al-Cu alloy. The control of added element size and distribution are very difficult because of the physical properties of Pb, Bi. The effect of master alloy compositions on microstructure and particle distribution was investigated. The ribbon shape of Pb-50wt% Bi master alloy showed the best results. And Ti addition improved even distribution of Pb, Bi particles. Particles grown from $L_2$ phase were considered to be the Pb, Bi compound.

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