Electrodeposition of Ni-Cr alloy on aluminum substrate^①

来源期刊：中南大学学报(英文版)2006年第3期

论文作者：杨余芳 龚竹青 邓丽元 罗北平 马玉天 阳征会

文章页码：219 - 224

Key words：nickel-chromium alloy; aluminium substrate; electrodeposition

Abstract: Ni-Cr alloys with mass fraction of 1.4% 23.9%Cr, 76.1% 98.6%Ni, and hardness of 70.5 80.5HR were electrodeposited on aluminium substrate from the trivalent chromium sulphate-chloride solution using citric acid as complexing agent. The aluminium was pretreated by means of degreasing and eroding, polishing and twice chemical immersion of zinc. The effects of electrodeposition parameters such as current density, temperature, pH value and bath concentration on the composition and hardness of deposits were investigated. The results show that the Cr content increases with the increase of current density and the decrease of temperature, and that it increases with the increase of pH value to a maximum and then decreases. The increase of Cr content leads to the increase of hardness of the Ni-Cr layers. The deposits with high Cr content are of good corrosion resistance. Good adherence of Ni-Cr deposits to aluminium substrate is obtained. The Ni-Cr alloys are the Ni-Cr solid solution with fcc crystalline structure. The Ni-Cr alloy deposits are fine, bright and smooth and compact.