Nitride nanophases in a plasma-assisted surface modified steel

Analysis of the growth of concomitant nitride layers produced by a post-discharge assisted process

“…Nitrogen concentration on the surface is a consequence of the balance between sputtering on the surface and nitrogen diffusion [19,20]. In contrast to nitriding processes with ammonia mixtures, in plasma assisted processes a fast evolution of nitrogen concentration takes place on the surface [21,22]. Nitrogen concentration on the surface, in plasma assisted processes, depends on molecular, neutral or ionized nitrogen, in different electronic, vibrational and rotational configurations.…”

“…It contrasts with ammonia nitriding, where the nitrogen potential is expressed in terms of the partial nitrogen pressure, considering references states at atmospheric pressure. Nevertheless, as in ammonia assisted processes, different authors have considered the growth of concomitant nitrided layers in terms of the thermo-chemical equilibrium between phases [19][20][21][22], which in turn are expressed through the solubility of the nitrogen in equilibrium in each phase [14,15,17,18].…”