烧结工艺对注射成形低膨胀合金性能的影响  

The Effect of Sinter Process on the Property of Low Expansion Alloys of Powder Injection Molding

作　　者：段柏华[1] 曲选辉[1] 章林[1] 汤春峰[1] 程彤[1] 

机构地区：[1]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《稀有金属材料与工程》2008年第4期701-704,共4页Rare Metal Materials and Engineering

基　　金：国家"863"计划(2006AA03Z113);教育部长江学者和创新团队发展计划(I2P407)

摘　　要：研究了烧结工艺对粉末注射成形4J32低膨胀合金性能的影响。结果表明,提高烧结温度或延长保温时间均能提高合金的致密度,但也会使其晶粒长大;而在氢气或高真空气氛下烧结能获得更好的性能。在最佳烧结工艺下,即烧结温度1350℃、烧结时间120min及氢气气氛,获得了高性能的PIM4J32低膨胀合金,其致密度为98.3%,在低于100℃的温度范围内,平均膨胀系数仅为0.3×10-6K-1,优于传统方法制备的合金性能及国家相应标准。该合金组织由奥氏体γ主体相及极少量的马氏体α相组成。The effects of sintering process on the properties of 4J32 low expansion alloys by powder injection molding were investigated. The results show that the relative density and the grain size of alloys increase with the sintering temperature or time. The properties of the alloy will be improved by sintering in atmosphere of hydrogen or high vacuum. After sintering under the optimum conditions, i.e. at temperature 1350 ℃ in atmosphere of hydrogen for 120 min, the PIM 4J32 low expansion alloys with high properties are obtained, which the relative density is 98.3% and the average thermal expansion coefficients below 100 ℃ is 0.3×10^-6 K^-1. The expansive property is better than that of alloys manufactured by traditional methods or GB specification. The microstructure of alloys is constituted of an, austenitite γ phase and α little martensite a phase.

关 键 词：粉末注射成形 低膨胀合金 热膨胀性 

分 类 号：TF124.5[冶金工程—粉末冶金]