工艺参数对连续碳纤维表面电磁搅拌化学镀镍的影响

Effect of Technological Parameters on Electroless Nickel Plating of Continuous Carbon Fiber Surface with Electromagnetic Stirring

目的解决连续碳纤维在镀覆过程中易出现黑心现象以及无法完全浸泡于镀液中的问题,制备镀层均匀的连续碳纤维镍镀层。方法引入外加电磁搅拌对连续碳纤维进行化学镀镍,研究了施镀时间、镀液温度、镀液pH值以及电磁搅拌转速对连续碳纤维表面微观形貌及镀层沉积速率的影响规律。结果当搅拌转速一定时,随着施镀时间、镀液温度、镀液pH值的不断增加,碳纤维表面镀层逐渐变得均匀完整,且镀层厚度逐渐增大。但当施镀时间超过20 min,镀液温度超过75℃,镀液pH值超过8时,镀层表面沉积了大量形状不一的胞状镍颗粒,形成粗糙的表面形貌。镀层的沉积速率随着镀液温度、镀液pH值的升高而增大。当搅拌转速由200 r/min增加到300 r/min时,镀层的沉积速率随着搅拌转速的增加而不断增大;当搅拌转速由300 r/min增加到400 r/min时,镀层的沉积速率随着搅拌转速的增加而不断减小。结论电磁搅拌辅助连续碳纤维化学镀镍的最佳施镀工艺参数为:施镀时间15~20 min,镀液温度75℃,镀液pH为8,搅拌转速200~250 r/min。采用此工艺参数能获得表面致密、均匀完整的镍镀层。

The work aims to solve the problem that continuous carbon fibers are prone to black core during plating and cannot be completely immersed in plating bath,so as to prepare uniform nickel coating on continuous carbon fibers surface.Electroless nickel plating was conducted on continuous carbon fibers with electromagnetic stirring.The effects of plating time,bath temperature,bath pH and electromagnetic stirring speed on the surface morphology and deposition rate of continuous carbon fibers were studied.When stirring speed was constant,with the increase of plating time,bath temperature,and bath pH value,the carbon fiber surface coating became uniform and complete gradually,and the coating thickness increased gradually;but when the plating time exceeded 20 minutes,the bath temperature exceeded 75℃,and the bath pH value exceeded 8,a large number of cellular nickel particles with different shapes were deposited on the coating surface,and then a rough surface morphology was formed.The deposition rate of the coating increased with the increase of bath temperature and bath pH.When the stirring speed increased from 200 r/min to 300 r/min,the deposition rate of the coating increased with the increase of stirring speed.However,when the stirring speed increased from 300 r/min to 400 r/min,the deposition rate of the coating decreased with the increase of the stirring speed.The optimum process parameters of electroless nickel plating on continuous carbon fibers surface with electromagnetic stirring are plating time of 15 to 20 minutes,bath temperature of 75℃,bath pH value of 8,and stirring speed of 200~250 r/min.The nickel coating obtained under the optimum technological conditions is compact,uniform and complete.