铝合金表面预处理及其镀镍工艺优化

摘要

本实验分别采用打磨、混合碱处理、水合肼处理和电晕处理四种方式对AA5052铝合金基体表面进行预处理,探讨了预处理方式对铝合金表面润湿性和表面形貌的影响,并在此基础上对铝合金表面镀镍工艺参数进行优化.通过接触角仪和扫描电子显微镜对镀层润湿性以及表面形貌进行表征,得到最佳化学镀镍条件:镀液温度为75℃,镀液pH值在6.2～6.4之间,化学镀时间40min.通过循环伏安法(CV)探索得到了最佳电化学镀镍条件:电镀时间为240s,电流密度为5 mA/cm2,镀液温度为60℃.实验表明,该实验条件下可以得到理想的镍镀层,且该方法可以广泛应用于其他相关的材料研究领域.%We studied the effects of surface morphologies and wettabilities with different pretreatments (polishing treatment,mixed alkali treatment,hydrazine hydrate treatment,corona treatment) on AA5052 aluminum alloy surface and finalize the optimum pretreatment method.On the basis of comparison tests,the optimum process conditions of nickel plating on AA5052 surface were determined.The surface morphologies and wettabilities were characterized by using scanning electron microscopy (SEM) and telescopic goniometer.The results show that the best electroless nickel plating conditions in this study are as follows:the temperature of the plating bath is 75℃,the pH value is 6.2-6.4 and the plating time is 40 minutes.By cyclic voltammetry,the best nickel plating was obtained under the conditions of 240s nickel plating time,current density of 5 mA/cm2 at 60℃.The results show that an ideal nickel plating can be prepared under the optimum experiment conditions,and this method is also meaningful for other relevant material engineering fields.