Effect of Heat Treatment Temperature on the Spectral Properties of Cu-Ni Coating.

Abstract

Cu-Ni coatings were prepared on the surface of nickel by electrodeposition method, and Cu-Ni coatings were heat-treated in 25-900 °C. Heat-treated Cu-Ni coatings were characterized with scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDAX) and X-ray diffraction (XRD) techniques, respectively. Effects of heat treatment temperature on the spectral properties of Cu-Ni coatings were studied. The surface of Cu-Ni coating is composed of the nodules. The nodules of Cu-Ni coating surface become smaller with the increase in heat treatment temperature in 25-600 °C. The nodules of Cu-Ni coating surface become smaller and the dividing line between the nodules becomes more blurred with the increase in heat treatment temperature in 600-900 °C. The contents of copper in Cu-Ni coating decrease from 82.52 at % to 78.30 at % with the increase in heat treatment temperature in the range of 25-900 °C; the contents of nickel in Cu-Ni coating increase from 17.48 at % to 21.70 at % with the increase in heat treatment temperature in the range of 25-900 °C. The crystal structure of Cu-Ni coating is Cu0:8lNi0.19 cubic crystal structure. The crystal structure of the CuO0.81Ni0.19 becomes more complete with the increase in heat treatment temperature in 25- 300 °C. Part of crystal structure of the Cu0.81AlNi0.19 can turn Cu0.8lNi0.19 cubic crystal structure into Cu3.8Ni cubic crystal structure, and is advantageous to Cu3.8Ni (311) and Cu0.81Ni0.19 (311) growth with the increase in heat treatment temperature in 600-900 °C.