An Auger sputter profiling study of nitrogen and oxygen ion implantations in two titanium alloys

Abstract

AbstractSamples of two titanium alloys, Ti–6Al–4V and Ti–15V–3Cr–3Sn–3Al, were ion implanted with a combination of nitrogen (N+) and oxygen (O+). For each alloy, implantation parameters were chosen to give implanted nitrogen concentrations of ∼10 or 50 at.%, from a depth of 100 nm to a depth of 400 nm. In all but one case, dual energy (200 keV and 90 keV) implantations of nitrogen were used to give a relatively uniform nitrogen concentration to a depth of 300 nm. In each case, oxygen was implanted at 35 keV, following the nitrogen implantation, to give an oxygen‐enriched region near the surface. The implanted samples were then examined by Auger electron spectroscopy (AES) combined with argon ion sputtering. In order to determine the stoichiometry of the nitrogen‐implanted regions, it was necessary to determine the N KVV contribution to the overlapping N KVV and Ti LMM Auger transitions. It was also necessary to correct for the ion‐bombardment‐induced compositional changes that have been described in an earlier study of titanium nitride thin films. The corrected AES depth profiles were in good agreement with theoretical predictions.