纳米SiO_2对汽车用铝硅镁系合金化学镀Ni-P合金镀层性能的影响

Influence of Nano-SiO_2 on Properties of Ni-P Alloy Coating Prepared by Electroless Plating on Surface of Al-Si-Mg Alloy for Automobile

以汽车用铝硅镁系合金(牌号ZAlSi7MgA)为基体,采用化学镀方法制备了Ni-P合金镀层和Ni-P/SiO_2复合镀层。采用扫描电镜、X射线能谱仪和电化学工作站等仪器,研究了纳米SiO_2对Ni-P合金镀层的表面形貌、物相组成、硬度、耐磨性及耐蚀性的影响。结果表明:与Ni-P合金镀层相比,Ni-P/SiO_2复合镀层具有更好的性能。这与纳米SiO_2对Ni-P合金镀层起到的强化作用有关。铝硅镁系合金化学镀Ni-P/SiO_2复合镀层后,其硬度提高5倍以上,耐磨性和耐蚀性也都得到提高,磨损速率明显降低,电荷转移电阻升高。

Ni-P alloy coating and Ni-P/SiO2 composite coating were prepared by electroless deposition on Al-Si-Mg alloy （ZAlSi7MgA） substrate for automobile. The influence of nano SiO2 on the surface morphology, phase composition, hardness, wear resistance and corrosion resistance of Ni-P alloy coating was investigated by scanning electron microscope, X-ray energy dispersive spectroscopy and electrochemical workstation. Results showed that, compared with Ni P alloy coating, Ni-P/SiO2 composite coatings has better properties due to the reinforcement effect of nano-SiO2 incorporated in Ni-P alloy coating. Electroless plating of Ni-P/SiO2 composite coating improves the hardness, wear resistance and corrosion resistance of Al-Si-Mg alloy. The hardness was improved by more than five times, the wear rate was significantly decreased and charge transfer resistance was increased.