复合电沉积工艺参数对镍晶微铸件表面性能的影响

Effect of Combined Electro-deposition Parameters on Surface Performances of Nickel Micro Electroforming Parts

目的将超声波、磁场引入到微电铸过程中,改善电沉积镍晶微构件的表面性能。方法改变电流密度、脉冲占空比、超声波功率、磁场强度的方向和强度,进行电沉积镍晶微铸件,分析这些工艺参数对微铸件表面形貌和显微硬度的影响。结果微铸件的显微硬度随磁场强度的增大而显著提高,随着阴极电流密度、超声波功率及脉冲占空比的增大呈现出先升高、后下降的规律,其中脉冲占空比对电铸层显微硬度的影响较弱。优选的工艺参数为:垂直磁场强度0.8 T,阴极电流密度2 A/dm2,超声波功率240W,脉冲占空比20%。结论引入超声波和磁场后可优化电沉积环境,细化电铸层晶粒尺寸,改善电铸层微观形貌,提高微铸件显微硬度。

Objective In order to improve the surface properties of electro-deposited nickel micro-electroforming parts, ultrason- ic and magnetic fields were introduced into the micro electroforming process. Methods Current intensity, pulse duty cycle, ultra- sonic power, direction and intensity of magnetic field strength were altered during the electro-deposition of nickel micro-electroforo ruing parts, and the effects of the above parameters on the performance of the surface morphology and microhardness of the micro- electroforming parts were analyzed. Results The micro-hardness of the micro-casting part increased significantly along with the in- crease of the magnetic field intensity, while first increased and then decreased along with the increasing current intensity, pulse du- ty cycle and ultrasonic power, among which the pulse duty cycle had weaker effect on the micro-hardness as compared to the other parameters. The optimized parameters were： vertical magnetic field intensity 0.8 T, cathode current density 2 A/dm2 , ultrasonic power 240 W, and pulse duty cycle 20%. Conclusion Electrodeposition environment could be optimized after introducing ultra-sound and magnetic fields so as to refine the grain size, improve the electrofomled layer morphology and enhance the microhardness of the microcasting parts.