The Influence of Nitrogen Implantation on the Hydrogen Distribution in Titanium Observed by Nra and Xps

Abstract

ABSTRACTTitanium has a strong chemical affinity and can absorb and store large amounts of hydrogen, which causes embrittlement of the material. Ion implantation is applied to improve wear behavior e.g. of titanium alloys, which are used for load bearing components of hip and knee joint prostheses. Nitrogen implantation influences the hydrogen content in the near surface region of a commercially available pure titanium. 150 keV 15N-ions were implanted at RT into titanium samples with a fluence of 6 × 1017 ions/cm2 and subsequently annealed at 500°C under high vacuum conditions. For comparison N was also implanted at a sample temperature of 500°C. Concentration depth profiles of implanted nitrogen and accumulated hydrogen were measured with Nuclear Reaction Analysis (NRA) and compared to nitrogen and titanium depth profiles obtained with X-ray Photoelectron Spectroscopy (XPS). The results indicate a relation between hydrogen concentration and the formation of Ti-N bonds.