放电等离子烧结原位制备TiC/Ti_2AlC复合材料及室温力学性能评价  

In-Situ Fabrication of TiC/Ti_2AlC Composite by Spark Plasma Sintering-Reactive Sintering (SPS-RS) Method and Its Mechanical Property

作　　者：施璐[1,2] 张建峰[1] 王连军[1] 江莞[1] 陈立东[1] 

机构地区：[1]中国科学院上海硅酸盐研究所高性能陶瓷和超微结构国家重点实验室,上海200050 [2]中国科学院研究生院,北京100049

出　　处：《稀有金属材料与工程》2009年第A02期533-535,共3页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(50625414;50821004);上海市优秀学科带头人计划(08XD14046);上海市纳米专项(0852nm03300)

摘　　要：以Al4C3、Ti和石墨粉为原料(Ti、Al、C的摩尔比为6:1:3),利用放电等离子烧结(SPS)技术通过原位反应制备出TiC/Ti2AlC的复合材料。结果表明,基体相TiC的晶粒尺寸在2～5μm左右,反应生成的Ti2AlC颗粒尺度纵向长度为4～10μm,横向宽度为1～2μm,且弥散均匀分布在基体中。三元层状相Ti2AlC的引入大大提高了复合材料的力学性能,复合材料的维氏硬度HV为11GPa,断裂韧性KIC为5.3MPa.m1/2,抗弯强度σf为(470+50)MPa,弹性模量E为(228+30)GPa。通过压痕法观察了裂纹扩展路径,讨论了材料的断裂机制和增韧机制。材料以沿晶断裂为主,伴随少量穿晶断裂。A mixture of Ti, Al4C3 and graphite powders was adopted to synthesize the TiC/Ti2AlC composite using the spark plasma sintering-reactive synthesis method. The molar ratio of Ti： Al： C=6：1：3 was selected. The main microstructure consists of TiEAlC grains with 4-10μm in length and 1-2 μm in width and TiC grains with 2-5 μm. The composite shows improved mechanical properties at room temperature. The HV, Kic, σf and E is 11 GPa, 5.3 MPa·m^1/2, （470±50） MPa, and （228±30） GPa respectively. The origin and propagating path of cracks under stresses were investigated by indentation method and SEM. The result shows that the cracking mechanism of TiC/Ti2AlC composites is mainly intergranular crack accompanied by slight transcrystalline crack.

关 键 词：SPS TiC TI2ALC 力学性能 断裂机制 

分 类 号：TB331[一般工业技术—材料科学与工程]