Low energy-high t1ux (1,2 keV, 1016cm−2s−1) nitrogen ion implantation and high flux plasma torch nitriding (1021cm−2s−1) of AISI 304 L stainless steel have been carried out in the temperature range 400° C-600° C. Thick nitrided layers of high nitrogen content (25–30 at %) have been formed and the nitrogen depth profiles determined by nuclear resonance analysis (NRA) and/or glow discharge optical spectroscopy (GOOS). The phases formed were identified by X-ray diffraction at glancing incidence. Below 430° C, the formation of a solid solution or expanded austenite γN phase has been observed; for higher temperature, the precipitation of chromium nitride occurs together with the formation of a α bcc Fe (Ni) phase. An important increase of hardness was obtained at both temperatures as well as a significant and durable wear resistance.