电子束增材制造技术用Ti-Ni预合金粉末性能研究  

Properties of Ti-Ni Pre-alloyed Powder Used for Electron Beam Melting

作　　者：任德春 张慧博[1] 李述军[1] 侯文韬[1] 王健[1] 金伟[1] 杨锐[1] Ren Dechun;Zhang Huibo;Li Shujun;Hou Wentao;Wang Jian;Jin Wei;Yang Rui(Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China)

机构地区：[1]中国科学院金属研究所,辽宁沈阳110016 [2]中国科学技术大学材料科学与工程学院,辽宁沈阳110016

出　　处：《稀有金属材料与工程》2020年第9期3218-3224,共7页Rare Metal Materials and Engineering

基　　金：中国科学院战略性先导科技专项(XDA22010103)。

摘　　要：采用DSC、SEM和XRD等测试手段研究和分析了电子束增材制造(EBM)技术用53~106μm Ti-Ni预合金粉末的性能及其随热处理温度和热循环次数的变化规律。结果表明:预合金粉末粒度呈正态分布,粉末内部填充及球形度良好,适于EBM打印使用;随热处理温度的升高预合金粉末相组成不发生变化但组织和成分变得均匀,内应力和位错被消除,晶粒尺寸长大,使得其550℃热处理后加热和冷却过程由多步相变转变为单步相变,650℃热处理后相变点开始保持稳定,而750℃热处理后达到最佳微烧结状态;预合金粉末在750℃烧结热循环和保温过程中相组成、单步相变行为和相变点均不发生变化,具有良好的热循环稳定性;底板及粉末层采用750℃预热温度成功制备出表面状态良好的Ti-Ni合金实体样品。The properties of pre-alloyed powder have an important influence on the additive manufacturing process,especially for Ti-Ni alloys with special shape memory effects.However,there are limited reports on the studies for the variation of Ti-Ni pre-alloyed powder with heat treatment temperatures and number of thermal cycles.In this work,the phase transformation behavior,micro structure and phase composition of 53~106μm Ti-Ni pre-alloyed powder used for electron beam melting(EBM)were studied using the differential scanning calorimeter,X-ray diffraction,and scanning electron microscope.The results show that the powder has good particle size distribution,internal filling and spherical topography,and suitable for EBM process.The structure and composition become uniform,internal stress and dislocation are eliminated and crystal grain size grows with the increase of heat treatment temperature,which causes the original multi-step phase transformation to one-step phase transformation during the heating and cooling process after 550℃and the phase transformation points maintain a stable state after 650℃heat treatment.The phase composition is not changed during the heat treatment process and the powder has best sintering state at 750℃.The phase composition,one-step phase transformation behavior and phase transformation points are all not changed for the powder during 750℃thermal cycles test,indicating good thermal cycling stability.Ti-Ni solid samples with good surface condition are successfully prepared under 750℃preheating temperature for bottom plate and powder layer.

关 键 词：Ti-Ni预合金粉末 电子束增材制造 热处理 热循环 相变行为 

分 类 号：TF123.9[冶金工程—粉末冶金]