Current status of supersaturated surface engineered S phase materials

Abstract

The present paper reviews the scientific development of the understanding of S phase. It is now known that S phase formation is an example of paraequilibrium phenomena. A necessary but not sufficient condition for S phase formation is the presence of a face centred cubic (fcc) structure at least in part with structure in the starting alloy. An essential requirement is for a nitride forming element to be present, particularly Cr. After surface engineering with carbon, nitrogen or carbon and nitrogen to generate supersaturated solid solutions, the various tribological, corrosion, mechanical and microstructural studies are reviewed for the various alloy systems. The current industrial status of S phase technology on an international basis is examined and the potential for its acceptance in China is discussed.

Keywords:

• STAINLESS STEELS
• EXPANDED AUSTENITE
• S PHASE
• LOW TEMPERATURE PLASMA ALLOYING