4^th European Mechanics of Materials Conference on Processes, Microstructures and Mechanical Properties

J. Phys. IV France 11 (2001) Pr4-189-Pr4-196
DOI: 10.1051/jp4:2001424

Study of the martensitic transformation on a Cr-Ni-Mo-Al-Ti steel for different thermomechanical paths

F. Azzouz¹, G. Cailletaud¹, F.D. Fischer², A. Pineau¹ and K. Tanaka<sup>3

1</sup>  Centre des Matériaux de l'École des Mines de Paris, UMR 7633 du CNRS, BP. 87, 91003 Evry cedex, France
²  Montanuniversität Leoben, Institut für Mechanik, Franz-Joseph Strasse 18, 8700 Leoben, Austria
³  Department of Aerospace Engineering, Tokyo Metropolitan Institute of Technology, Asahigaoka 6-6, 191-0065 Hino/Tokyo, Japan

Abstract
The purpose of this paper is a study of the onset of martensitic transformation under complex thermomechanical paths, and the development of TRIP plasticity. The final aim is to provide a criterion, written in terms of temperature and stresses, to be used for determining both the initiation and the kinetics of martensite transformation and the related TRIP strains. The model will be written on a macroscale, so that only one scalar value is introduced to represent all the martensite variants. The specimens are thin tubes tested on a tension-torsion machine, so that multiaxial stress paths can be applied. The transformation is produced either during cooling under constant stress or at a given temperature in tensile tests. Both types of tests allow to characterize the onset of the transformation; on the other hand, a full modeling of the test under constant load is proposed, and compared with a classical approach. The new constitutive equations have been implemented into the F.E. code ZeBuLon.

© EDP Sciences 2001