J. Phys. IV France 07 (1997) C5-411-C5-416
The Influence of External Stresses on the Transformation Behaviour in a Fe-Mn-Si AlloyM. Andersson1, R. Stalmans2 and J. Agren1
1 Royal Institute of Technology, Department of Materials Science and Engineering, 10044 Stockholm, Sweden
2 Katholieke Universiteit Leuven, Departement of MTM, de Croylaan 2, 3001 Heverlee, Belgium
The influence of external stresses on the transformation behaviour has been studied for a polycrystalline Fe-31Mn-5Si alloy exhibiting the γ → ε martensitic transformation. Samples have been loaded at temperatures above the Ms temperature, cooled with a constant external load to a temperature below the Ms temperature and subsequently heated without load to a temperature above the As temperature of the alloy. Stress, strain and temperature have been continuously measured and transformation temperatures and strains have been determined from the change in strain during the transformation. It has been found that the Ms temperature during cooling with load is not influenced by 0.3-2 % plastic pre-deformation of the austenite whereas there is a substantial increase in the transformation strain, i.e. variants with a favourable orientation are enhanced by pre-strain of austenite.
© EDP Sciences 1997