利用Ni与不同粒度的Cr颗粒通过复合电镀的方法分别制备了Ni-7.5Cr (平均粒度为21nm)、Ni-10.9Cr (平均粒度为39nm) 和Ni-12.4Cr (平均粒度为2.4µm)的复合镀层。Ni-Cr纳米复合镀层与Ni-Cr微米颗粒镀层相比，其颗粒分布更为均匀，颗粒间距减少2—3个数量级。900℃恒温氧化实验结果表明：复合微米颗粒的Ni-Cr镀层只形成NiO膜，不能形成连续的Cr2O3膜，氧化速率很快；而Ni-Cr纳米复合镀层，由于能形成连续的Cr2O膜，氧化速率显著降低，并且这种颗粒尺寸效应随粒度越细越明显。文中对颗粒尺寸效应进行了探讨。
Ni-7.5Cr,、Ni-10.9Cr、Ni-12.4Cr composites were prepared by means of co-electrodeposition of Ni matrix with three kinds of Cr particles in average size of 21 nm,39 nm, and 2.4µm, respectively. Compared to the electrodeposited microparticles-dispered composite coating (EMCC), the electrodeposited nanoparticles-dispered nanocomposite coatings (ENNCs) exhibits more homogeneous distribution of Cr particles and the interparticle spacing is approximately two orders of magnitude lower. The ENNCs have a very low oxidation rate at 900℃, due to the rapid formation of a continuous and compact chromia scale, whereas the EMCC exhibits a very poor oxidation resistance, due to the formation of porous NiO scale. For the ENNCs, the finer the Cr particles codeposited, the better the oxidation performance. The particles size effect on the oxidation behaviour of electrodeposited Ni-Cr composites is also discussed.
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