Substrate-induced stress and the transformation behavior of sputter-deposited NiTi thin films

Ti–50.5at.%Ni thin film sputter-deposited at 450 °C shows a multi-stage phase transformation sequence. The transformation temperatures of the substrate-attached film are slightly higher than that of the same thin film in freestanding condition. An unusual triangular stress–temperature loop is observed which is associated with the R-phase transformation.