(華南理工大學(xué) 機(jī)電工程系， 廣州 510640)
摘 要: 研究了等離子噴涂Ni基WC型自熔合金涂層爐熔處理前后的組織形態(tài)。結(jié)果表明，經(jīng)重熔處理后，涂層由富含孔隙、未熔顆粒的層狀結(jié)構(gòu)轉(zhuǎn)變?yōu)橹旅艿慕Y(jié)晶組織結(jié)構(gòu)，涂層與基材由機(jī)械咬合結(jié)合轉(zhuǎn)變?yōu)橐苯鸱磻?yīng)擴(kuò)散結(jié)合，涂層的內(nèi)聚強(qiáng)度和涂層/基材的結(jié)合強(qiáng)度都得以顯著改善。涂層的相組成在重熔前后變化不大，均主要由γ-Ni固溶體相， Ni-B(Ni2B)， Cr-B(CrB)， Ni-Si(Ni5Si2)和WC硬質(zhì)相等組成。由于等離子噴涂是一種快速凝固工藝，在噴涂態(tài)涂層中形成了部分非晶相，經(jīng)重熔處理后，非晶相發(fā)生完全晶化。
關(guān)鍵字: 自熔合金涂層； 等離子噴涂； 重熔處理；組織結(jié)構(gòu)
（Department of ElectroMechanical Engineering,
South China University of Technology,Guangzhou 510640, P.R.China）
Abstract:The WC+Ni base selffluxing alloy coating was fabricated by plasma sprayingand then remelted in furnace. The results show that, after being remelted, the coating's morphology changes from laminar structure containing some pores and unmelted particles to dense crystal structure, and the adhesion between coating and substrate transforms from mechanical combination to chemicometallurgical reaction combination, so the coating's cohesive strength and adhesive strength are improved remarkably. The remelted coating consists of γ-Ni, Ni-B(Ni2B), Cr-B(CrB), Ni-Si(Ni5Si2) and WC phases that are alike the one of plasma sprayed coating. A little amorphous phase lies in the plasma sprayed coating due to the rapid solidification process, and the amorphous crystallizes after remelting process.
Key words: self-fluxing alloy coating； plasma spraying； re-melting process； microstructure
