WC/Ni60A等离子喷涂层的相结构分析

STRUCTURE OF PHASES IN WC/Ni60A COMPOSITE COATING SPRAYED BY PLASMA

利用Ｘ射线衍射，ＳＥＭ； ＥＤＡＸ； ＴＥＭ及选区电子衍射等手段研究了 ＷＣ／ Ｎｉ６０Ａ等离 子喷涂层的显微组织及其相结构结果表明：涂层组织呈片层状。在Ｎｉ基合金片层中的镍基固溶体上析出 了大量高度弥散分布的 Ｍ_７Ｃ_３， Ｍ_２３Ｃ_６及 Ｎｉ_３Ｂ；由于等离子喷涂温度较高， ＷＣ大部分熔化并与 Ｎｉ 包覆层互溶，发生高温分解。

The morphology and structure of the phases in plasma-sprayed WC/Ni60A composite coating were studied by X-ray diffraction, SEM, EDAX, TEM and electron diffraction etc. The results showed that plasma-sprayed WC/Ni60A composite coating takes lamellar structures as characteristics, and a lot of highly dispersed M_7C_3, M_23C_6 and Ni_3B particles precipitated on Ni-base solid solution in Ni60A layer. As plasma spraying temperature was higher, the most of WC were co-dissolved with Ni cladding coating, meanwhile WC decomposed easily, the highly dispersed M_6C and α-W_2C particles were formed in Ni cladding WC layer.