Free Access
Issue
J. Phys. IV France
Volume 11, Number PR8, Novembre 2001
Fifth European Symposium on Martensitic Transformations and Shape Memory Alloys
Page(s) Pr8-451 - Pr8-456
DOI https://doi.org/10.1051/jp4:2001875
Fifth European Symposium on Martensitic Transformations and Shape Memory Alloys

J. Phys. IV France 11 (2001) Pr8-451-Pr8-456

DOI: 10.1051/jp4:2001875

Multiple martensitic transformation induced by coherent precipitation in NiTiCo melt spun ribbons

Ph. Vermaut1, 2, M. Larnicol2, M. Hÿtch1, P. Ochin1 and R. Portier1, 2

1  Centre d'Études de Chimie Métallurgique, UPR 2801 du CNRS, 15 rue Georges Urbain, 94407 Vitry-sur-Seine, France
2  Laboratoire de Métallurgie Structurale, École Nationale Supérieure de Chimie de Paris, 11 rue Pierre et Marie Curie, 75231 Paris, France


Abstract
A study of a multiple martensitic transformation observed in melt spun ribbons cast with a relatively low melt temperature is presented. Transmission electron microscope (TEM) investigations allow the identification of fine plate-like precipitates as a metastable Ti2Ni phase. Analysis of high resolution microscope (HREM) images reveals the presence of a strain field in the matrix surrounding the precipitates which promote the martensitic transformation. Grow and loss of coherency of these precipitates coincides with disappearance of the higher temperature martensitic transformation. Attribution of the multiple transformation to this precipitation is discussed.



© EDP Sciences 2001