Influence of the microstructure on the resulting 18R martensitic transformation of polycrystalline Cu-Al-Zn thin films obtained by sputtering and reactive annealing

P. DOMENICHINI; A.M. CONDÓ; F. SOLDERA; M. SIRENA; N. HABERKORN

MATERIALS CHARACTERIZATION

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2016 vol. 114 p. 289 - 295

1044-5803

We report the influence of the microstructure on the martensitic transformation in polycrystalline Cu-Zn-Al thin films with 18R structure. The films are grown in two steps. First, Cu-Al thin films are obtained by DC sputtering. Second, the Zn is introduced in the Cu-Al thin films by the annealing them together with a bulk Cu-Zn-Al reference. The crystalline structure of the films was analyzed by X-ray diffraction and transmission electron microscopy. The martensitic transformation temperature was measured by electrical transport using conventional four probe geometry. Itwas observed that temperatures above 973 K are necessary for zincification of the samples to occur. The resulting martensitic transformation and its hysteresis (barrier for the transformation) depend on the grain size, topology and films thickness.