氩弧熔覆原位合成高温抗氧化性涂层

Prepare in-situ synthesis high temperature oxidation resistance coating by argon arc cladding

为克服石墨在723 K以上会发生氧化反应的不足,在石墨电极表面,采用氩弧熔覆技术,以Si和Ti粉末为原料,制备原位合成的高温抗氧化复合涂层。通过热力学计算和扫描电子显微镜分析,利用X射线衍射仪进行涂层物相分析,确定涂层由SiC、TiC、TiSi、TiSi2和Ti5Si3陶瓷颗粒组成。结果表明:合金熔覆层与石墨基体的结合呈现一种连续的结合界面,没有明显的缺陷;1 573 K条件下灼烧60 min,氧化失重率为0.875%。

Aimed at overcoming the occurrence of insufficient graphite oxidation reaction over 723 K, this paper introduces the use of TIG cladding to prepare the in-situ synthesized high temperature oxidation resistance composite coating from the raw materials of Si and Ti powder on the surface of graphite electrode. The thermodynamic calculation, scanning electron microscope （SEM）, and X-ray diffraction （XRD） verify that the coating consists of SiC,TiC,TiSi,TiSi2,TiSSi3 ceramic particles. The results show that the combination of the cladding layer and the graphite matrix results in a kind of a continuous interface free from obvious flaws, as is evidenced by an oxidation weightlessness rate of 0. 875% resulting from the burning 60 rain at 1 573 K.