脉冲电铸镍-氧化钕纳米复合沉积层的工艺研究

A Study on the Process of Pulse Electroformed Ni-Nd_2O_3 Nanocomposite Deposits

电化学沉积层的制备是电铸技术的关键环节。本文采用脉冲电铸技术制备N i-Nd2O3纳米复合沉积层,考察了镀液中Nd2O3纳米颗粒添加量、平均电流密度、占空比、脉冲频率对纳米复合沉积层中Nd2O3含量及纳米复合沉积层显微硬度的影响,并对纳米复合沉积层的表面形貌进行了分析。结果表明,在镀液中Nd2O3纳米颗粒添加量20 g/L^30 g/L、脉冲平均电流密度2 A/dm2~4 A/dm2、占空比0.2~0.4和脉冲频率1000 Hz的条件下,可获得Nd2O3含量大的高硬度复合沉积层,并且沉积层表面平整、光滑,晶粒细小,组织均匀致密。

The preparation of electrochemical deposits is the key of electroforming method. Ni-Nd2O3nanocomposite deposits were prepared by pulse elcctroforming method. Effects of concentration of Nd2O3 nanoparticles in the bath, pulse average current density, duty cycle, pulse frequency on the Nd2O3 content in the nanocomposite deposits as well as the microhardness of nanocomposite deposits were evaluated. The surface morphology of Ni-Nd2O3 nanocomposite deposits were also analyzed. The results indicate that, under the conditions of nanoparticles concentration in the bath 20 - 30 g/L, pulse average current density 2 - 4 A/dm^2, duty cycle 0. 2 - 0. 4 and pulse frequency 1000 Hz, the Ni-Nd2O3 nanocomposite deposits exhibit higher contents of Nd2O3nanoparticles and high microhardness. Moreover, the Ni-Nd2O3 nanocomposite deposit has smooth morphology, refined crystal grain and compact microstructure.