Nitride formation was studied in various steels with different alloying ele
ments. Results of PI3 nitriding, r.f. nitriding with self bias and DC volta
ge at 300 and 400 degreesC were compared. It was found that nitriding of fe
rritic steels depends strongly on the formation of surface nitride layers.
The habit of the nitrides and the supersaturation of nitrogen is strongly i
nfluenced by the HV pulsing during PI3 and thus also the treatment depth an
d layer properties. (C) 2001 Elsevier Science B.V. All rights reserved.