机械合金化ODS钴基合金粉末的放电等离子烧结  

Spark Plasma Sintering of ODS Cobalt Base Alloy Powder by Mechanical Alloying

作　　者：汤春峰[1] 曲选辉[2] 周霆[2] 段柏华[2] 何新波[2] 秦明礼[2] 

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083 [2]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》2007年第8期1461-1464,共4页Rare Metal Materials and Engineering

基　　金：国家"863"计划资助项目(2003AA331140)

摘　　要：采用机械合金化(MA)和放电等离子烧结(SPS)技术制备了Y2O3弥散强化Co基合金,研究了高能球磨过程中粉末形貌和微观结构的变化规律以及机械合金化粉末的放电等离子烧结行为。结果表明:在球磨的初始阶段(≤8h),粉末粒度和晶粒尺寸显著减小,晶格畸变增大;球磨8h以后,粉末粒度、晶粒尺寸和晶格畸变的变化渐缓;但进一步延长球磨时间,使Y2O3弥散粒子的分布更加均匀。采用放电等离子烧结技术,在1100℃,10min条件下便可制备出相对密度>99%的合金试样,所得合金平均晶粒小于5μm,经过均匀化热处理后,合金的室温抗压强度和压缩延伸率分别达到1982MPa和27%,优于铸造钴基合金。Alloyed powder of Cobalt base alloy were prepared by mechanical alloying and bulk alloy was prepared by spark plasma sintering. The experimental results show that the sizes of particle and crystalline grain decrease and the distortions of lattice increase with the milling time during the first stage up to about 8 h, then trends to be slow down. A longer milling time is beneficial to get uniform distribution of Y2O3 nano-particles in the mixture. The relative density of sintered compact is over 99% by spark plasma sintering at 1100 ℃ for 10 min. Its average grain size is smaller than 5μm. After homogenization treatment at 1300 ℃, the alloy compressive strength and elongation at room temperature are 1982 MPa and 27%, respectively, superior to the cast cobalt base alloy.

关 键 词：机械合金化 放电等离子烧结 钻基高温合金 晶格畸变 

分 类 号：TF124.5[冶金工程—粉末冶金]