Ti_2AlC/TiAl复合材料的高温氧化性能研究  

Study on the Oxidation Properties of Ti_2AlC/TiAl Composites at High Temperatures

作　　者：岳云龙[1] 尹海燕[1] 屈雅[1] 苏通[1] 吴海涛[1] 

机构地区：[1]济南大学,山东济南250022

出　　处：《稀有金属材料与工程》2007年第5期853-856,共4页Rare Metal Materials and Engineering

基　　金：山东省自然科学基金重点项目资助(Z2003F02)

摘　　要：利用放电等离子烧结(SPS)技术,原位制备Ti2AlC/TiAl和Ti2AlC/TiAl(Nb,B)复合材料,并研究其在900℃和1000℃的高温氧化性能。研究发现,掺加Nb,B后复合材料的抗氧化性能明显提高,1000℃氧化30h时氧化层厚度为50μm～60μm,未掺入Nb,B时其厚度约为170μm。在氧化层和复合材料交界处结构疏松出现许多孔洞,Nb原子在高温时向表面层富集使复合材料抗氧化性能提高,富Nb层的存在即可以阻挡氧原子的继续渗入,又可以作为扩散障,减少Kirkendall效应;加入B后,组织明显细化,氧化反应初始阶段氧化物的形核增多。In this paper, the oxidation properties were studied at 900 ℃ and 1000 ℃ for the Ti2AlC/TiAl and Ti2AlC/TiAl （Nb, B） composites fabricated by spark plasma sintering （SPS） technology. It is shown that the oxidation resistances of composites were obviously improved by the addition of Nb and B, the thickness of oxide layer reduces from 170 μm to 50 μm-60 μm after oxidation at 1000℃ for 30 h. There were many holes at the interface of oxide layer and composites. The enrichment of Nb atoms to the surface at high temperature can improve the oxidation resistance of composites, as diffusion obstacle either stopping the infiltration of oxygen, or reducing the Kirkendall domino effect due to the existence of layers rich in Nb. The microstructure can be obvioursly refined because the nuclear formation was increased at the beginning of oxidation by adding B.

关 键 词：TI2ALC/TIAL复合材料 抗氧化性 高温 

分 类 号：TF124.5[冶金工程—粉末冶金] TG113.231[冶金工程—冶金物理化学]