Nitrogen implantation of metals

Abstract

Sixteen metals implanted to saturation with 300-keV N2+ ions have been studied using nuclear resonance broadening and Rutherford backscattering techniques to profile the implanted concentration. Blisters due to the implanted nitrogen were observed in Mg, Al, Ti, V, Cr, Nb, Mo, Ta, W, and AISI 304 steel but not in Cu, Zr, Ag, Hf, and Au. The nominal saturation concentration at maximum varied from 50 to 60 at. % for all cases except for Cu, Ag, and Au, where it was 20 at. %. The surface hardness was generally increased by a factor between 1.2 and 2.3. However, no increase was observed for Mo, Ag, and Au. The mononitride formation in Ti, Zr, and Hf was verified by x-ray diffraction. The formation of blisters and diffusion in the preparation of nitrides is discussed.