高密度光盘读取头用合金悬丝化学镀银的研究

Chemical silver plating on the copper alloy wires for high density optical pickup

利用化学液相反应在Cu合金悬丝基体上进行了化学镀银,研究了镀层的成分以及主盐浓度、反应时间对镀银悬丝导电性能的影响。随着硝酸银、葡萄糖浓度的增加,镀银悬丝的电阻率均表现为先降低,后升高;随反应时间增加,Ag层厚度增加,电阻率降低。当硝酸银浓度为30g/L、葡萄糖浓度为40g/L,反应时间为20min时,镀Ag层厚度为1.3μm,电阻率为7.0×10-6(Ω.cm);导电性比镀银前提高了20%。FE-SEM、EDS能谱对镀层的形貌、成分及厚度研究表明,镀层为纯金属Ag,无氧化物存在,Ag层与铜合金基体结合力良好,无裂纹、脱落等缺陷。该方法制得的镀Ag悬丝材料适合于高密度光盘读取头力矩器的使用要求。

Copper alloy wires with silver coating were prepared by chemical liquid plating.In this study,the effect of coating composition,main salt concentration and reaction time on the property of suspension wire were investigated.It was found that the resistivity of suspension wire firstly decreases and thereafter increases with the increase of silver nitrate,glucose concentration.The thickness of silver increases and the resistivity decrease with increasing plating time.When the concentration of silver nitrate is about 30g/L,the concentration of glucose is about 40g/L and the reaction time is 20min,the thickness of silver gets 1.3μm and the resistivity of sample reaches to 7.0×10-6（Ω·cm）.The conductivity has got about 20 percent increase compared with the sample without silver plating.The morphology,thickness,composition were characterized by Physics properties measurement system（PPMS,Quantum Design）and field emission-scanning electron microscope（FE-SEM）.The results show that the coating composition is pure silver without oxide.The binding force between the silver coating and the substrate is perfect and there are no defects such as crack,stripping,and so on.The suspension wires obtained from this method is suitable for the application at the optical actuator for high density optical storage.