摘要
Ti coating on A3 steel was successfully prepared by direct electrochemical reduction of high-velocity oxy-fuel （HVOF） thermally sprayed and room-temperature dip-coating titanium dioxide coating on A3 steel in molten CaCl2 at 850 ℃. The interfacial microstructure and mutual diffusion between coating and steel substrate were investigated using scanning electron microscopy （SEM） and energy dispersive X-ray （EDX） spectroscopy. The results show that the precursory TiO2 coating prepared by HVOF has closer contact and better adhesion with the A3 steel substrate. After electrolysis, all of the electro-generated Ti coatings show intact contact with the substrates, regardless of the original contact situation between TiO2 layer and the steel substrate in the precursors. The inter-diffusion between the iron substrate and the reduced titanium takes place at the interface. The results demonstrate the possibility of the surface electrochemical metallurgy （SECM） is a promising surface engineering and additive manufacturing method.
采用超音速火焰喷涂(HVOF)技术和室温提拉法在碳钢上制备致密和多孔两种TiO_2涂层,然后在CaCl_2熔盐中直接电化学还原TiO_2得到金属钛涂层,利用SEM、EDX等技术对涂层与基体界面的显微组织和金属互扩散行为进行研究。结果表明,与提拉法相比,虽然超音速火焰喷涂(HVOF)法制备的TiO_2涂层与碳钢基体有更强的附着力和更致密的结构,但二者熔盐电解还原后所得钛涂层与碳钢基体都有较好的结合,在界面处发生了铁、钛互扩散,表明表面电化学冶金(SECM)可能是一种颇具发展潜力的表面工程/增材制造方法。
基金
Projects(51071112,51325102)supported by the National Natural Science Foundation of China
