Ti_3SiC_2-TiSi_2-TiB_2熔覆复合材料在氩气退火过程中的相稳定性分析  

Analysis of phase stability for Ti_3SiC_2-TiSi_2-TiB_2 deposition composites during argon annealing

作　　者：闫文青[1] 刘升[1] 李虎虎 桂赤斌[2] 

机构地区：[1]武汉科技大学钢铁冶金及资源利用省部共建教育部重点试验室,武汉430081 [2]华中科技大学材料科学与工程学院,武汉430074

出　　处：《焊接学报》2018年第3期79-82,共4页Transactions of The China Welding Institution

基　　金：湖北省教育厅青年基金资助项目(Q20141103)

摘　　要：采用氩弧熔敷法制备了Ti_3SiC_2-Ti Si_2-Ti B_2复合材料,并对其在高温氩气退火过程中的相稳定性进行了分析.结果表明,Ti_3SiC_2相在氩气保护和1 450℃高温条件下具有稳定性,而原位合成的含碳的Ti Si_2(C_x)固溶体相在退火过程中通过原子扩散而发生分解,其转化产物主要为Ti_3SiC_2及少量的SiC稳定相.退火后,熔覆样品中Ti_3SiC_2的体积含量比退火前增加了4.8%.热力学计算结果表明,样品在退火过程中通过原子扩散引起的反应机制为Ti Si_2(C_x)→Ti_3SiC_2+SiC,并提出了Ti_3SiC_2-Ti Si_2-Ti B_2熔覆复合材料在退火过程中的原子扩散反应模型.退火试验分析结果表明,钨极氩弧熔敷法与高温退火相结合的复合工艺可以提高Ti_3SiC_2-Ti Si_2-Ti B_2熔覆复合材料的整体热稳定性.The stability of phases in the Ti_3SiC_2-TiSi_2-TiB 2 composites prepared by argon arc deposition during the high temperature annealing in argon was analyzed in this study. The results showed that the Ti_3SiC_2 phase was stable during annealing at 1 450 ℃ in argon,but in-situ synthesized solid solution phases such as TiSi_2 Cxdecomposed through atom diffusion during annealing. The transformed products were mainly composed of stable Ti_3SiC_2 and a small amount of SiC. After annealing,the volume content of Ti_3SiC_2 in the sample increased by 4. 8% comparing with non-annealing. The thermodynamic calculation results showed that the reaction mechanism through atom diffusion during annealing was TiSi_2 Cx→Ti_3SiC_2+ SiC. The atom diffusion reaction model of the Ti_3SiC_2-TiSi_2-TiB2 composites during annealing was proposed. The annealing experiment analysis results showed that the tungsten argon arc deposition combined with annealing process could improve the whole thermal stability of Ti_3SiC_2-TiSi_2-TiB 2 composites.

关 键 词：熔覆复合材料 氩气退火 相稳定性 

分 类 号：TG401[金属学及工艺—焊接]