XRD, XPS and SIMS investigations on electrodeposited nickel-phosphorous alloy coatings

Structural and chemical investigations on electrodeposited nickel-phosphorous alloy coatings by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and secondary ion mass spectroscopy (SIMS) are described. Electrodeposition of nickel-phosphorous coatings has been carried out galvanostatically in a hypophosphite bath at two different current densities, namely 20 and 80 mA cm(-2). XRD has shown a broad peak indicating an amorphous structure in both cases. XPS shows the presence of Ni2P compound. XPS also reveals the amount of phosphorous in both coatings to be around 10.20 wt.%. SIMS has shown that the coating deposited at lower current density (20 mA cm(-2)) has a broad coating-substrate interface, possibly due to some porosity in this coating. The presence of some oxygen contamination at the coating-substrate interface is also evidenced through SIMS in both cases. The usefulness of XPS and SIMS in the characterization of electrodeposited coatings is demonstrated.