Phase stability of AISI 304 stainless steel during sliding wear at extremely low temperatures

For applications at extremely low temperatures of a few Kelvin, austenitic FeCrNi alloys usually are employed due to their beneficial mechanical and magnetic properties. These properties depend on the stability of the austenitic microstructure, since transformation into martensite leads to a loss of ductility as well as to the formation of ferromagnetic regions. The necessary conditions for the transformation into martensite are present in case of components subjected to friction, e.g. in machine parts used for transportation of cryogens, especially of liquid hydrogen. The transformation behaviour at low temperatures is studied on friction stressed FeCrNi steel AISI 304 by magnetic measurements and by diffraction methods. (C) 2003 Elsevier B.V. All rights reserved.