TiSi_2提高TiB_2陶瓷烧结致密性机理研究  

Mechanisms of TiSi_2 Enhancing Sintering Densification of TiB_2 Ceramic

作　　者：马爱琼[1] 段锋[1] 

机构地区：[1]西安建筑科技大学材料与矿资学院,西安710055

出　　处：《硅酸盐通报》2015年第6期1679-1683,共5页Bulletin of the Chinese Ceramic Society

基　　金：陕西省自然科学基金(2013JM6013)

摘　　要：以TiSi2作为烧结助剂,采用热压烧结制备了TiB2陶瓷。对烧结试样进行了XRD、SEM与EDS分析,对TiB2-x%TiSi2系统进行了热力学计算分析,探讨了TiSi2促进TiB2陶瓷低温烧结致密的机理。结果表明:添加6.0wt%TiSi2作为烧结助剂,可以使TiB2陶瓷在1650℃热压烧结致密。TiSi2促进TiB2陶瓷烧结致密机理为:一是TiSi2熔点低于烧结温度,通过液相传质提高了烧结速率;二是通过高温烧结反应,形成了高熔点的Ti5Si3相以及SiO2玻璃相,SiO2以玻璃相的形式填充气孔并促进液相传质,使坯体致密。In the present research, TiB2 ceramic was prepared by hot-pressing sinter using TiSi2 as a sintering aid. XRD, SEM and EDS analysis method were employed to study sintering samples. Thermodynamic calculation analysis was used in TiBz-x% TiSi2 system. The mechanism that TiSi2 can promote densification of TiB2ceramic at low temperature was probed. The investigation results show： TiB2 ceramic can be dertsified at 1650 ~C by hot-pressing sinter if 6.0wt% TiSi2 was used as sintering aid. The mechanisms that TiSi2 promotes sintering densification of TiB2 ceramic include two aspects. Firstly, because of melt temperature of TiSi2 lower than sintering temperature, mass transfer can realize by liquid phase to enhance sintering rate; Secondly, by sintering reaction at high temperature, the mass phase such as TisSi3 and SiO2 can product, among these, TisSi3 has high-melting-point and SiO2 phase can fill the pore and accelerate liquid mass transfer.

关 键 词：TIB2陶瓷 TISI2 机理 烧结致密 

分 类 号：TQ174[化学工程—陶瓷工业]