High nitrogen steels are known for their combination of good strength, toughness and high plastic work capacity which makes these steels suitable for wear applications. If the hardness of the steels can be improved further, by precipitation hardening, the wear properties of the steel may be enhanced, provided that the plastic work capacity of the steels is not compromised. Niobium and vanadium are known to form a fine dispersion of precipitates in low alloy steels and it is the aim of the present work to imitate this process in high nitrogen stainless steels and thereby improve hardness. It is shown that various forms of precipitation are possible in high nitrogen steels, including the formation of niobium and vanadium carbonitrides at high temperatures and chromium nitrides at lower temperatures. The formation of fine niobium and vanadium carbonitrides results in an improvement of the hardness of the steel, but at the expense of the plastic work capacity which decreases. It is shown that appropriate selection of niobium and vanadium levels and heat treatment is fundamental to balance improved hardness of the steel with a good plastic work capacity.
|Number of pages||10|
|Journal||Materials Science Forum|
|Publication status||Published - 1999|