镁合金化学复合镀Ni-P/纳米SiC工艺的研究

A Research on the Process of Electroless Composite Ni-P-Nano SiC Plating on Magnesium Alloy

在AZ 91D镁合金表面制备Ni-P/纳米SiC化学复合镀层。探讨镀液中纳米SiC微粒的质量浓度对镀速、复合镀层性能等的影响。利用扫描电镜观察镀层表面形貌,采用能谱分析仪进行镀层表面成分的定性分析,采用显微硬度计测试镀层硬度,并对不同工艺下获得的镀层进行快速磨损实验。结果表明:镀液中添加适量的纳米SiC微粒,镀速和镀层硬度都有显著的提高。当镀液中纳米SiC的质量浓度为9 g/L时,镀速可达到25.6μm/h;当镀液中纳米SiC的质量浓度为7 g/L时,镀层的维氏硬度可达到9380 MPa;同时镀层的耐磨性能相比于Ni-P合金镀层的也有显著提高。

An electroless Ni-P-nano SiC composite coating was prepared on the AZ 91D magnesium alloy surface.The effects of the mass concentration of nanometer SiC particles in the bath on plating rate,properties of composite coating were investigated.The surface morphology of the coating was observed by SEM.The qualitative analysis of the coating composition was carried out by EDAX.The hardness of the coating was tested by micro-hardness testing equipment.A fast wear experiment was performed on the coatings obtained under different conditions.The results show that the plating rate and hardness of composite coating can be increased greatly when appropriate amount of SiC particles are added.The plating rate and hardness of the coating can reach 25.6 μm/h and 9 380 MPa when the nanometer SiC content in the plating bath is 9 g/L and 7 g/L respectively.Compared with Ni-P coating,the wear resistance of the composite coating increase obviously as well.