铜合金表面激光诱导原位反应制备颗粒增强Co基复合合金涂层

Particle reinforced Co-based composite alloy coating produced by laser inducing in-situ synthesis on the surface of copper alloy

以含有定量纳米Al粉的Co基新型合金为涂层的原材料,在Cu-Cr合金表面利用Nd:YAG固体激光器诱导原位反应制备陶瓷相增强Co基复合涂层。采用金相显微镜、扫描电镜和显微硬度等分析技术,对所制备样品涂层的结构和形成机制进行了研究。结果表明:通过激光诱导原位反应,在铜合金表面制备出了组织细小、界面呈冶金结合的陶瓷相增强Co基涂层;涂层的显微硬度由基体表面显微硬度HV87提高到HV426;纳米Al粉的加入为激光诱导原位反应制备Co基涂层提供内部热源,弥补了铜合金基体因导热快而带来的能量损失,充分诱导涂层内的物质发生化学反应,有利于Co基复合涂层的形成;涂层中原位生成的陶瓷相直径小于2.0μm,弥散分布在涂层中起到骨骼强化作用。

A new kind of Co-based alloy coating powder containing certain amount of nano-A1 powder was designed. The ceramic phases in the coating were produced by YAG pulse laser inducing in-situ synthesis. The microstructure morphology and the forming mechanism of the coating were studied by means of scan electronic microscope, optical micrograph analysis techniques and micro-hardness tester. By the pulse laser inducing in-situ synthesis, the interfaces of the thin coatings are metallurgically combined and the ceramic particles are well dispersed. The micro-hardness of the Co-based composite alloy coating is promoted from HV87 to HV426. The added nano-Al supplies the interior heat-fountain, which compensates for the energy loss caused by the quick heat transmission of Cu-based alloy. The added nano-A1 can fully induce the interior chemical reaction , which improves the composite coating forming easily. Ceramic particles are less than 2.0 μm in diameter and dispersed in the strengthened coating.