脉冲喷射电沉积纳米晶镍镀层的工艺优化

为了在硫酸盐体系中得到工艺稳定、光亮、硬度高的纳米晶镍镀层,进行了4因素(电流密度、喷速、脉冲频率和占空比)3水平正交试验.优选出制备微观结构镀层的最佳的工艺条件是:喷速1000 L/h,电流密度20.4 A/dm2,占空比40%,脉冲频率1000 Hz;制备硬度镀层的最佳的工艺条件是:电流密度15.3 A/dm2,占空比40%,喷速1400 L/h,脉冲频率1000 Hz.分析了各因素对镀层晶粒尺寸和硬度的影响.结果表明,电流密度对镀层质量影响较大,而选择合适的喷速使镀层具有优异的硬度和比较小的晶粒尺寸.

Optimization of Jet-Electrodeposited Nickel Coating in Pulse Current

In this paper,the bright nanocrystalline nickel deposit with stability was synthesized by pulse-jet electrodeposition from sulphate system.The effect of operating parameters,such as current density,jet speed,pulse frequency and duty cycle,on the structure and properties of nickel coating was discussed by orthogonal design.The results from X-ray diffraction(XRD) and micro-hardness tests show that the best technology process is current density of 15.3 A/dm2,jet speed of 1 400 L/h,duty cycle of 40% and pulse frequency of 1 000 Hz.The nickel coating also exhibits better micro-hardness performance and comparatively smaller grain size.