脉冲喷射电沉积纳米晶镍工艺优化研究

采用脉冲喷射电沉积方法在钢基体表面制备了纳米晶镍镀层,研究了占空比、频率、平均电流密度对镀层硬度的影响,并通过正交试验对工艺参数进行优化,用扫描电镜和X-射线衍射仪对镀层表面形貌和晶粒尺寸进行分析。结果表明,制备纳米晶镍镀层的优化工艺参数为:平均电流密度39.8 A/dm2、频率1 000 Hz和占空比20%,此时镀层最致密,硬度最高(530.6 HV),纳米晶镍平均晶粒尺寸最小(13.7 nm)。

Optimization of Preparation Parameters for Pulse Jet Electrodepositing Nanocrystal Nickel Coatings

The nanocrystal nickel coatings were prepared by pulse jet electrodepositing on the substrate of 0.45% carbon steel.The effects of pulse duty factor,frequency and average current density on the microhardness of nanocrystal nickel coatings were investigated,and the preparation parameters were optimized using orthogonal experiment.The surface morphology and crystal size of the coatings were analyzed by SEM and XRD.The results show that the optimal preparation parameters are 39.8 A/dm2 of average current density,1 000 Hz of frequecy and 20% of pulse duty factor.The nickel coating prepared under the optimal conditions is most compact,and has highest microhardness of 530.6 HV and smallest crystal size of 13.7 nm.