Origin of nitrogen depth profiles after laser nitriding of iron

In spite of its technological importance, the basic mechanisms of laser nit riding of metals and alloys are hardly understood. The nitrogen depth profi les achieved by laser nitriding of pure iron were measured with high accura cy by resonant nuclear reaction analysis and described by two superimposed diffusion profiles. Using simple estimates, together with the results of ma rker experiments and laser treatments in N-15-isotopically enriched atmosph eres, the development of these profiles with the number of pulses can be si mulated in excellent agreement with the experimental results. (C) 1999 Amer ican Institute of Physics. [S0003-6951(99)04201-1].