脉冲参数对 NiW 基带表面电化学抛光质量的影响

目的研究提高Ni W合金基带表面质量的脉冲电化学最佳抛光工艺。方法以磷酸为主要抛光酸剂,以甘油为缓冲剂配置抛光液,采用脉冲电化学抛光技术,研究电流密度、脉冲频率、脉冲占空比对Ni W基带的表面抛光效果的影响。通过扫描电镜和原子力显微镜对抛光后的基带表面微观形貌进行表征,获得最佳脉冲电化学抛光工艺。结果最佳工艺为:平均电流密度25 A/dm2,脉冲频率毫秒级(1000Hz以上),脉冲占空比1∶4,抛光时间10 min。扫描电镜结果表明,抛光后的基带表面平整致密,轧制和热处理产生的条纹、晶界等缺陷都被消除,在此抛光工艺下,可以有效降低Ni W基带表面粗糙度,提高基带表面质量。原子力显微镜测试4μm×4μm范围内的表面平均粗糙度为几个纳米,表明抛光基带表面非常平滑,达到镜面效果。结论最佳抛光工艺下,可以显著改善Ni W基带的表面质量,获得好的基带表面状态,满足涂层导体对金属基带材料表面质量的要求。

Effects of Pulse Parameters on Electrochemical Polishing Quality of the Surface of NiW Substrate

ABSTRACT:Objective To develop an optimal pulse electrochemical polishing technology to improve the surface quality of Ni5%W alloy substrate. Methods Using environment friendly phosphoric acid and glycerol buffer additives as the polishing system. Pulse electrochemical polishing technique was used to study the influences of pulse parameters, namely current density, pulse fre-quency and pulse duty cycle on the surface polishing effects of NiW substrate. The microstructure of the polished substrate surface was characterized by scanning electron microscope and atomic force microscope. The best pulse electrochemical polishing process was obtained according to the test results. Results The best pulse electrochemical polishing process conditions were as following:Jm=25 A/dm2 , f =1000 Hz, duty cycle 1:4, t=10 min. The SEM test results showed that the baseband surface was smooth and compact after polishing. Rolling and heat treatment defects such as streaks and grain boundary were eliminated. The surface rough-ness of NiW substrate was effectively reduced and the surface quality was improved by the optimized polishing process. The AFM tests results showed that the average surface roughness was a few nanometers within the 4 μm×4 μm range, showing that the pol-ished substrate surface was very smooth, reaching mirror state. Conclusion The optimal polishing process could significantly im-prove the surface quality of the substrate and achieve good substrate surface state. It could meet the requirements of coated conduc-tor on the surface quality of metal substrate materials.