Abstract:TiPdNi thin films were prepared by magnetron sputtering onto unheated glass and silicon substrate. Atomic force microscope, energy-dispersive X-ray microanalyzer, X-ray diffractometer, differential scanning calorimeter and optical microscope were used to characterize the films. It is found that the surface morphology of the films change during the sputtering process and a shift of about 3%Ti(mole fraction) content from the center to the edge of the substrate occurs. The freestanding asdeposited films undergo crystallization followed by three kin d s of cooling conditions. For all these heat-treated films, B2→B19→B19′ two-stage phase transformation takes place. Many Ti₂Ni and Ti₂Pd type of precipitates are detected in the films. The constraint films on silicon substrate are crystallized at high temperature. After crystallization, the films show a two-way shape memory effect.

Key words: TiPdNi；thin film；sputter deposition；martensitic transformation； shape memory effect