【摘要】 以正硅酸乙酯（TEOS）为前驱体,采用溶胶-凝胶法制备SiO₂包覆铝粉。利用红外光谱、激光粒度分析仪、X射线衍射仪和扫描电镜等手段,对所制备样品的物相结构、表面形貌和粒径进行表征。将所制备的SiO₂包覆铝粉用于电沉积Ni-Co-Al复合镀层。结果表明:原料铝粉发生严重的团聚现象,在0.1 mol/L盐酸和去离子水溶液中都产生较大的析氢量;SiO₂包覆铝粉的析氢量几乎为零,具有较好的分散性;在酸性镍钴镀液中添加SiO₂包覆铝粉获得了铝含量高的Ni-Co-Al复合镀层。该镀层在900℃有良好的抗氧化性能,可用作高温环境下工作的零部件的表面防护镀层。更多还原

【Abstract】 SiO₂ coated aluminum powers were prepared by sol-gel method with tetraethyl orthosilicate（TEOS）as precursor.The phase structure,morphology and particle size of the samples were characterized with FTIR spectra analysis,laser particle size analysis,X-ray diffractometer（XRD） and scanning electron microscopy（SEM）.Then,the SiO₂ coated aluminum powders were used for electrodeposition of Ni-Co-Al composite coating.Results indicated that for the untreated aluminum powers,the agglomeration phenomenon occurred and a large amount of hydrogen was generated in 0.1 mol/L.hydrochloric acid solution and deionized water,respectively.Whereas SiO₂ coated aluminum powers had a good dispersion and its hydrogen evolution amount was nearly zero in above two solutions.The Ni-Co-Al composite coating with high aluminum content was successfully prepared by adding SiO₂ coated aluminum powders in acid nickel-cobalt bath,which exhibited a good oxidation resistance at 900 ℃ and therefore,the composite coating could be used as the surface protective coating of the parts working at high temperature.更多还原