(1. 莆田學(xué)院 機(jī)電工程學(xué)院，莆田 351100)
(2. 北京工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院，北京 100124)
摘 要: 為了制備出可對(duì)比的兩類(lèi)復(fù)合涂層，采用TiB2和Ni+TiB2分別作為熔覆材料，在鈦合金表面通過(guò)激光原位熔覆制備復(fù)合涂層。采用XRD、SEM、EPMA與摩擦磨損儀等實(shí)驗(yàn)手段，對(duì)合成的鈦基復(fù)合涂層進(jìn)行研究。結(jié)果表明：采用TiB2為熔覆材料時(shí)，可獲得TiB2顆粒與TiB短纖維增強(qiáng)鈦基復(fù)合涂層。采用Ni+TiB2為熔覆材料時(shí)，可生成NiTi合金填充在TiB2顆粒與TiB短纖維周?chē)玊iB2顆粒尺寸和TiB短纖維長(zhǎng)度都得以減小。通過(guò)微動(dòng)磨損測(cè)試，發(fā)現(xiàn)引入NiTi合金和TiB2顆粒及TiB短纖維復(fù)合強(qiáng)化，無(wú)法有效抵抗微動(dòng)磨損性能。這主要與摩擦接觸區(qū)的溫度超過(guò)NiT超彈性變形的溫度區(qū)間，且NiTi合金無(wú)法使裂紋擴(kuò)展曲折及硬度低相關(guān)。最后，探討了該復(fù)合涂層在抗微動(dòng)磨損與干滑動(dòng)磨損過(guò)程中的差異性。
關(guān)鍵字: 激光熔覆；TiB短纖維；NiTi合金；摩擦；磨損
（1. School of Mechanical and Electrical Engineering, Putian University, Putian 351100, China;
2. College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124, China）
Abstract:In order to prepare two kinds of composite coatings for comparison, TiB2 and Ni+TiB2 were, respectively, used as cladding materials, and the composite coatings were prepared by laser in-situ cladding technique on the surface of titanium alloy. The synthesized titanium-based composite coatings were studied by XRD, SEM, EPMA and friction and wear instruments. The results show that TiB2 particle and TiB short fiber reinforced titanium-based composite coating can be obtained when TiB2 is used as the cladding material. When Ni+TiB2 is used as the cladding material, the NiTi alloy can be formed to be filled around the TiB2 particles and the TiB short fibers, but the size of the TiB2 particles and the length of the TiB short fibers are all reduced. Through the fretting wear test, it is found that the composite reinforcement of NiTi alloy and TiB2 particles and TiB short fiber can not effectively resist the fretting wear performance. There are three reasons for this: the temperature of the friction contact zone exceeds the temperature of the NiTi superelastic deformation, the crack propagation cannot be deflected by the introduction of NiTi, the hardness of the NiTi alloy is low. Finally, the difference between the anti-friction wear and dry sliding wear of the composite coating was discussed.
Key words: laser cladding; TiB short fiber; NiTi alloy; friction; wear
