Ni/ZrO_2复合镀层电沉积行为与耐高温氧化性能的研究

Electrodeposition Behavior and High Temperature Oxidation Resistance of Ni/ZrO_2 Composite Deposit

通过电化学试验、高温氧化试验、扫描电镜及X 射线衍射 ,研究了电沉积Ni/ZrO2 复合镀层的电化学行为和添加微粒对镍镀层高温抗氧化性能和组织结构的影响。研究结果表明 ,在瓦特 (Watts)镀液中加入ZrO2 微粒使电镀时阴极电流密度明显降低 ,阴极电位与时间 (E t)、阴极电流对时间 (I t)的关系曲线变化趋势不大 ,但I t曲线抖动加快 ;高温氧化试验结果表明 ,ZrO2 微粒可以使复合镀层的高温抗氧化能力明显提高 ;Ni/ZrO2 复合镀层与瓦特镍镀层的高温氧化规律基本满足W =ktn;扫描电镜能谱分析则证实 :在 80 0℃高温氧化过程中 ,明显存在铜向镍镀层中的扩散 ,这可能有利于增强镀层与基底之间的粘合。X 射线衍射表明 ,在高温氧化时 ,镀层表面主要生成NiO产物。

The effects of ZrO\-2 particles on the microstructure and high temperature oxidation resistance of the composite Ni/ZrO\-2 deposit was studied. The cathodic current density could be evidently decreased by the addition of ZrO\-2 particles, but the \%I-t\% of \%E-t\% curves were not distinctly changed. The experimental results showed that the existence of ZrO\-2 particles in the composite would improve the high temperature resistance of the coating. The weight gain curves of the composite coating and also nickel coating in high temperature oxidation experiments were in accordance with \%W\%=k\%t\%\+n. It was shown by the energy dispersive analysis that the diffusion process occurred between copper substrate and composite coating at 800℃ could enhance the coherent force between the two. The main product on composite coating after being oxidized at 800℃ was verified by X-ray analysis.