钨基重合金注射成形产品变形原因及其控制

来源期刊：中南大学学报(自然科学版)1999年第1期

论文作者：曲选辉 李志林 李益民 黄伯云

文章页码：49 - 51

关键词：钨基重合金;变形;粉末冶金;金属注射成形

Key words：tungsten-based heavy alloy; distortion; powder metallurgy; metal injection molding

摘    要：研究了MIM重合金产品在注射、脱脂和烧结3个阶段的变形原因及其解决方法,结果表明：注射时由于成形坯的冷却收缩和合模线的存在使成形坯的形状和大小与模具形腔有差异；粘结剂中聚丙烯质量分数高于30%时可保证溶剂萃取脱脂时样品不变形；先在1350℃进行低温固相烧结,然后在1530℃进行高温液相烧结,可较好地消除烧结过程中填料对产品内孔孔径收缩的阻碍作用.

Abstract: The distortion of MIM heavy alloy compacts during injection molding, debinding and sintering is analyzed. The results show that the size of the green compacts is different from that of die cavity due to the parting line and the shrinkage of compacts during cooling, the compact distortion during solution debinding can be avoided if the content of polypropylene in the binder is over 30%, and the stemming effect of filler on the shrinkage of inner holes during sintering can be eliminated through two-step sintering process.