锌粉颗粒形状对机械沉积无结晶镀层结构的影响

以球状锌粉和片状锌粉为原始锌粉借助于机械镀工艺制备了无结晶锌防护层，运用光学显微镜（OM）、扫描电子显微镜（SEM）观察了镀层的结构形貌；采用XRD技术分析了镀层的物相组成；采用贴滤纸法进行了镀层的孔隙率测试。研究结果表明，片状锌粉制备的镀层比球状锌粉制备的镀层表面要平滑、光亮。球状锌粉制备的镀层中锌粉颗粒呈紧密堆积，部分锌粉颗粒发生塑性变形；片状锌粉制备的镀层中的锌粉颗粒呈层片状叠加，镀层中锌粉颗粒没有发生明显塑性变形。两种形状锌粉制备的镀层均为锌基多相混合体系，镀层中没有固溶体、化合物等合金相产生，属于锌基复合镀层。锌粉颗粒形状对镀层中颗粒之间的结合机理没有显著影响，两种镀层中锌粉颗粒间均以机械咬合为主。

Effects of particle shapes of zinc metal on the structure of mechanically deposited coating

Zinc coatings were prepared by mechanically deposition method with spherical zinc particle and lamellar zinc particle, respectively. OM and SEM were employed to observe the structure of the coating. XRD was employed to analyze the phase of the coating. The porosity of the coating was tested by porosity testing. The results show that the coatings deposited with lamellar zinc exhibit better surface properties than that obtained by using spherical zinc. The coating deposited with spherical zinc is a mosaic composite. Only a part of spherical zinc particles have obvious plastic deformation in the coating. The coating deposited with lamellar zinc is a lamellar structure, in which zinc particles experience almost no plastic deformation. The coatings obtained by spherical zinc or lamellar zinc are zinc matrix metallic composite, have no any alloy compounds or solid solution formed in building of the coating. The particle shapes of zinc particles have no effects on bonding that is mechanical bonding in the coating.