TiB-TiB_2陶瓷复合材料的放电等离子烧结致密化  

Densification Research of TiB-TiB_2 Composites in Situ Synthesized by Spark Plasma Sintering

作　　者：张朝晖[1] 罗杰[1] 黄橙骋[1] 王富耻[1] 李树奎[1] 

机构地区：[1]北京理工大学材料学院,北京100081

出　　处：《北京理工大学学报》2010年第4期492-495,共4页Transactions of Beijing Institute of Technology

基　　金：国家部委基金资助项目(9140A12050209BQ0137)

摘　　要：通过放电等离子烧结技术制备了新型的TiB-TiB2陶瓷复合材料,测试了复合材料的微观组织和力学性能,研究了复合材料微观组织的演化规律,揭示了复合材料的放电等离子烧结致密化机理.烧结前期,通过放电效应使Ti发生高温溅射,在TiB2颗粒间形成流线型丝状连接;随着温度的升高,TiB2颗粒与熔融的钛金属之间发生化学反应,生成的TiB呈棒状生长;烧结后期,随着烧结温度的提高,在焦耳热效应和烧结压力的共同作用下,塑性变形和固相扩散成为主要烧结机制,使复合材料迅速达到致密.TiB-TiB2 ceramic composites are in situ synthesized by spark plasma sintering technique under a pressure of 50MPa,with sintering temperature ranging from 800℃ to 1700℃ and a heating rate of 150℃/min,using Ti and TiB2 powders.Microstructures and mechanical properties of the composites sintered at different temperatures were investigated.According to the microstructure evolution of the composites,the description of the sintering process can be divided into 3 stages： splashing of metal Ti under the discharge effect,reaction of the molten Ti with TiB2,and rapid densification of the composites due to the rapid solid-state diffusion and large plastic deformation result from the Joule heating effect and pressure loading effect.

关 键 词：TiB-TiB2陶瓷复合材料 放电等离子烧结 致密化机理 

分 类 号：TG146.2[一般工业技术—材料科学与工程]