双向脉冲快速电沉积非晶态Ni-P/Al_2O_3复合镀层

采用双向脉冲电沉积法制备出高P非晶态Ni-P/Al_2O_3复合镀层,利用扫描电镜(SEM)和能谱分析(EDS)方法考察镀层的微观形貌和化学组成,采用X射线衍射技术(XRD)表征镀层的相结构,并通过分析金属镀层和复合镀层的电化学测试结果,评价不同种类镀层的耐腐蚀能力。结果表明:与直流电沉积法相比,双向脉冲电沉积法可将镀层中的P含量提高至12.06%(质量分数),有利于非晶态Ni-P合金镀层的形成。采用双向脉冲法制备的Ni-P/Al_2O_3复合镀层比直流电沉积法制备的Ni-P/Al_2O_3复合镀层更平整、结晶更致密。脉冲电沉积法制备的非晶态Ni-P合金镀层具有更好的耐蚀性,而且复合微粒Al_2O_3的加入,对进一步提高非晶态Ni-P合金镀层的耐蚀性有积极作用。

Fast Electrodeposition of Amorphous Ni-P/Al2O3 Composite Coatings Deposited by Bi-directional Pulse

The amorphous Ni-P/Al2O3 composite coatings with high P content were deposited using the bi-directional pulse electrodeposition.The micrographic morphology and chemical composition of the coatings were examined using the scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) analysis.Also,the phase structure of the coating was characterized using the X-ray diffraction (XRD).By analyzing the electrochemical test results of the coatings,the corrosion resistances of different types of deposits were evaluated.The results show that compared to the direct current (DC) plating,the P content in the Ni-P alloy coatings increases to 12.06 ％ (mass fraction) by bidirectional pulse electrodeposition,which facilitates the formation of the amorphous Ni-P alloy coatings.The PC plating can produce a finer and denser Ni-P/Al2O3 composite coatings with more compact crystallization than that deposited by DC.The Ni-P alloy coatings deposited by the pulse electrodeposition has a better corrosion resistance,and adding composite particles of Al2O3 can further contribute to improving the corrosion resistance of the amorphous Ni-P alloy coatings.