  In this study we report a method for the preparation of freestanding
magnetocaloric thin films. Non-stoichiometric Heusler alloys Ni-Mn-Sn,
Ni-Co-Mn-Sn and Ni-Co-Mn-Al are prepared via sputter deposition. A sacrificial
vanadium layer is added between the substrate and the Heusler film. By means of
selective wet-chemical etching the vanadium layer can be removed. Conditions
for the crystallization of Vanadium layers and epitaxial growth of the Heusler
films are indicated. Magnetic and structural properties of freestanding and
as-prepared films are compared in detail. The main focus of this study is on
the influence of substrate constraints on the Martensitic transistion.
