Nanocrystalline platinum layer deposited on NiTiCu shape memory strip
University of Silesia, Institute of Materials Science, Bankowa 12, 40-007 Katowice, Poland
2 Academy of Sciences of the Czech Republic, Institute of Physics, Na Slovance 2, Prague 18221, Czech Republic
3 ICMPE CNRS - Université Paris 12 (UMR 7182), 15 rue Georges Urbain, 94400 Vitry-sur-Seine, France
The Ni25Ti50Cu25 shape memory strip was covered by thin nanocrystalline platinum layer. Structure of the layer was studied by means of X-ray diffraction and transmission electron microscopy. Transformation temperatures were determined using differential scanning calorymetry (DSC). The studies show that the layer reveals nanocrystalline structure with average crystalline size of 44 nm. Lattice distortion was relatively low –0.19%. Almost 25% of total grains are oriented along 〈111〉 direction. It was stated that the nanocrystalline platinum layer does not limit martensitic transformation in the covered strip, which reveals one step reversible martensitic transformation from the parent B2 phase to the orthorhombic martensite B19 phase. Also no influence of the layers on the shape recovery was noticed.
© EDP Sciences, Springer-Verlag, 2008