电流密度对超临界CO2流体镍电铸层表面性能和过程参数的影响

采用非离子表面活性剂,进行超临界CO2流体(SCF-CO2)电铸金属镍的研究,分析电流密度对CO2超临界流体镍电铸层微观组织、显微硬度、阴极电流效率、沉积速率、铸层厚度的影响。结果表明,随着阴极表面电流密度从3A/dm2逐渐增加至9A/dm2,体系电流效率快速下降,金属镍电铸层的显微硬度、沉积速率、铸层厚度不断增大。在压力为10MPa,温度为323K,电流密度为5A/dm2时,镍电铸层的显微硬度、铸层厚度、阴极电流效率、沉积速率分别为7.01GPa、30.5μm、94.51%、51.85mg/cm2·h,与传统电铸方法相比较,SCF-CO2电铸法制备的镍电铸层表面平整、微观组织致密。

Effect of Current Density on Surface Properties and Process Parameters of Nickel Film Electroformed under Supercritical CO2 Fluids

The experiment of nickel electroforming with non-ionic surfactant was carried out under supercritical CO2 fluid. The effects of current density on microstructure, Vickers hardness, current efficiency, depositing rate and thickness were discussed. The results indicate that the microhardness, the depositing rate, the thickness of the nickel films gradually increase while the current efficiency decreases with the current density growing from 3 A/dm2 to 9 A/dm2. In the cases of 10 MPa, 323 K and 5 A/dm2, the microhardness, the current efficiency, the depositing rate and the thickness of nickel films are 7.01 GPa, 94.51%, 51.85 mg/cm2·h and 30.5 μm, respectively. Compared to the conventional electroforming method, the nickel film by SCF-CO2 electroforming has more flat surface and more dense microstructure.