Depth analysis of electrodeposited iron–nickel and copper–zinc alloy coatings by glow discharge emission spectroscopy

Abstract

AbstractAlloy coatings of FeNi and CuZn electrodeposited on Cu and Fe substrates were analysed with glow discharge spectrometry (GDS) to determine the coating weights of the alloying elements and the concentration depth profile. The coating weight of each element was determined from the integrated intensity which is the area under the intensity‐time curve of the element. A linear relationship is observed between the GDS integrated intensity and the coating weight indicating that GDS is able to quantify the alloy coating. The depth profile obtained was however not the true depth profile because of the effects of sputter broadening (due to differing sputtering rates between the central portion and the edges) and possibly bombardment‐induced segregation (diffusion of zinc towards surface due to the effects of Ar+ bombardment and surface segregation due to heating of the sample) for the CuZn alloy coatings. The use of references of a series of FeNi and CuZn block samples were considered for the determination of the alloy composition. While it is practical for the FeNi system, it is not for the CuZn system because of the effects of surface segregation and bombardment‐induced segregation.