PIM充模过程的边界层效应及机理分析  

Boundary layer effect of powder injection molding filling flow process and mechanics analysis

作　　者：王玉会[1] 曲选辉[1] 张勇[1] 何新波[1] 赵丽明[1] 郑洲顺[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《粉末冶金技术》2008年第4期254-259,共6页Powder Metallurgy Technology

基　　金：国家自然科学基金重点项目(50634010);国家重点基础研究发展规划项目(G2000067203);国家杰出青年科学基金(50025412)

摘　　要：通过对注射坯进行局部密度测试及采用SEM方法观察注射坯截面上粉末-粘结剂的分布状态,揭示了PIM充模过程的边界层效应。将边界层及两相流理论应用于PIM充模过程的研究,分析表明:普通的边界层效应及粉末、粘结剂粘度和密度的差异带来的偏析现象是产生PIM边界层效应的原因。凡是影响模壁吸引熔体分子及影响熔融注射料粘度的因素均会对PIM的边界层效应产生影响。模拟结果表明:随着注射温度由430K升高到450K,PIM的边界层效应变得明显;而入口的注射料流量由60cm3/s增加到80cm3/s,这种效应反而略有减轻。The boundary layer effect of the powder injection molding filling flow process was studied through local density measurement and SEM. The boundary-layer theory and two-phase flow theory were applied for analysis the PIM filling flow process, it shows that the reasons creating the boundary layer effect are the ordinary boundary layer effect and the segregation caused by the difference of viscosity and density between powder and binder. All factors affecting the adsorption of the die wall and the viscosity of the feedstock affect the boundary layer effect of PIM . The effect will be marked gradually as the temperature of injection increases from 430K to 450K, but it will be weakened as the flow rate increases from 60cm^3/s to 80cm^3/s.

关 键 词：粉末注射成形 边界层效应 局部密度 边界层 两相流 

分 类 号：TQ320.662[化学工程—合成树脂塑料工业] V211.41[航空宇航科学与技术—航空宇航推进理论与工程]