镀液中金属杂质离子对电镀镍层性能的影响

Effect of Metallic Impurities in the Electroplating Solution on Nickel Coatings

向镍电镀原液中引入2 g/L的Co^(2+),Cr3+,Mn^(2+),Fe^(2+),Cd^(2+),Zn^(2+)等离子,通过电镀得到不同的镀层.X射线衍射(XRD)、X射线光电子能谱(XPS)及扫描电子显微镜(SEM)的结果表明,不同金属离子对镍沉积影响不同,金属杂质离子的存在会使镀层中晶粒尺寸变小,影响镍镀层的均匀性和致密度.通过阴极极化曲线、计时电位和交流阻抗等方法探讨了含有不同金属杂质的镀液在电镀过程中电化学行为的规律性.通过镀液的浓度梯度、耐腐蚀、耐热循环及耐高温等实验获得了不同条件下金属杂质在镀液中所允许的浓度范围.

To study the influence of impurities on the coating quality,2 g / L of Co^（2＋）,Cr^（3＋）,Mn^（2＋）,Fe^（2＋）,Cd^（2＋）,Zn^（2＋）were introduced into the nickel plating solution,respectively. The results of X-ray diffraction（ XRD） revealed that the obtained nickel coatings were of different growth orientation. The results of scanning electron microscopy（ SEM） showed that the presence of metallic impurities made coating grain size smaller,different metallic impurities made different influence,then the brightness and density of the obtained coatings had great difference. Regularity of electrochemical behavior of electroplating solution with different metallic impurities was investigated by catholic polarization, chronopotentiometry and electrochemical impedance spectroscopy. Through the concentration gradient experiment,corrosion experiment,heat cycle and high temperature experiments,the critical concentrations of metallic impurities were guaranteed to obtain high quality Ni coatings for different use.