Microstructural Design for Improved Mechanical Behaviour of Advanced Materials
J. Phys. IV France 10 (2000) Pr6-21-Pr6-26
Correlation between microstructure and transformation behaviour in bulk and rapidly solidified shape memory alloysC. Elgoyhen, M. Larnicol, P. Ochin and R. Portier
Métallurgie Structurale, ENSCP, 11 rue Pierre et Marie Curie, 75231 Paris cedex, France, and CECM - CNRS, 15 rue Georges Urbain, 94400 Vitry-sur-Seine, France
The martensitic transformation is a structural phase transformation associated with a shape change of the unit cell. Although this shape change is minimized for thermoelastic martensitic transfomation, it has to be accommodated by the surrounding material. As a consequence, the transformation characteristics strongly depend on the microstructure of the material. Designing the properties and characteristics of Shape Memory Alloys, requires a control of its microstructure during processing. Different processing methods leading to different characteristics of SMAs are examined in this investigation. In particular, the origin of the multiple martensitic transformation is discussed in terms of dislocation cells or coherent precipitate distribution present according to the processing of the material.
© EDP Sciences 2000