Hot deformation of duplex stainless steels

Duplex stainless steels (DSSs) have become established materials, successfully employed in many industrial applications. Their combination of mechanical properties and corrosion resistance is particularly appreciated in the petrochemical field. Hot deformation of these two-phase materials is still a critical point because the different mechanical response of austenite and ferrite often leads to the formation of edge cracks. In the present research, two DSSs with different nitrogen contents, i.e. EN 1.4462 and EN 1.4410, have been subjected to uniaxial hot compression tests in a wide range of temperatures and strain rates. The microstructural changes produced as a consequence of the distinct test conditions have been analyzed by means of optical and electron microscopy. The characteristics of high temperature plastic flow of both DSSs are interpreted in terms of the classical hyperbolic sine equation. The results are finally discussed considering the intrinsic two-phase nature of the materials studied. (C) 2003 Elsevier Science B.V. All rights reserved.