汽车用AZ31B镁合金表面化学沉积Ni-P/SiO_2镀层及腐蚀分析

Electroless Deposition of Ni-P/SiO_2 Coating on AZ31B Magnesium Alloy for Automobile and Corrosion Analysis

采用化学镀方法在AZ31B镁合金表面沉积Ni-P/SiO_2镀层。以Ni-P/SiO_2镀层的腐蚀速率为考察指标,采用正交试验确定了最优化学镀工艺参数为:镀液温度80℃,化学镀时间100min,SiO_212g/L。对最优Ni-P/SiO_2镀层进行腐蚀分析。结果表明:与AZ31B镁合金相比,相同条件下最优Ni-P/SiO_2镀层表面更难发生腐蚀,腐蚀速率低且腐蚀坑小。最优Ni-P/SiO_2镀层能够提高汽车用AZ31B镁合金的耐蚀性。

Ni-P/SiO2 coating was deposited on AZ31B magnesium alloy for automobile by electroless plating process. Taking the corrosion rate of Ni-P/SiO2 coating as inspection index, the optimal electroless plating process parameters, that is bath temperature 80 ℃, electroless plating time 100 min, SiO2 12 g/L, were determined by orthogonal experiment. Corrosion of the optimal Ni-P/SiO2 coating was analyzed. Results showed that, compared with AZ31B magnesium alloy, corrosion was hard to occur on the surface of the optimal Ni-P/SiO2 coating, the corrosion rate was low and the corrosion pit was small. The optimal Ni-P/SiO2 coating can improve the corrosion resistance of AZ31B magnesium alloy for automobile.