利用行星球磨原理,以NiCrAlY粉末为原料,采用机械合金化(MA)工艺在碳钢管状零件内壁制得NiCrAlY合金涂层,并利用CO2激光器对涂层进行激光重熔处理.采用X射线衍射分析(XRD)、扫描电镜分析(SEM)、能谱分析(EDS)及维氏硬度试验研究了激光重熔前后涂层的显微组织及性能变化.结果表明,在球磨转速为400 r/min,球磨时间为10h的工艺条件下,在零件内表面形成结合性较好的涂层,其厚度约为40μm；激光重熔后,其组织结构更均匀致密.%A novel mechanical alloying (MA) method is developed to prepare NiCrAlY coatings on the inner surface of a tubular component using a planetary ball mill. A CO2 laser is applied to remelt the mechanically alloyed coating. The phase constitution, microstructure, composition and microhardness of the as-coated and laser remelted coatings are investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and hardness testing. The results reveal that the NiCrAlY coating with a thickness of 40 jum is successfully deposited on the substrate by setting a bowl rotation speed of 400 r/min and a ball milling time of 10 h. The laser remelting resulted in significant dilution of coating due to inter diffusion of atoms. After laser remelting, a denser and more homogeneous structure is obtained.
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