Combinatorial materials science methods are used to find new shape memory materials with optimized functional properties. Shape memory thin film materials libraries are fabricated via magnetron sputtering. These materials libraries show a continuous gradient of parameters like annealing temperature, film thickness or composition on one wafer. Together with high-throughput measurement techniques it is possible to illuminate the influence of the varying parameters on a material’s properties.
The Co-Ni-Ga materials system is promising for future actuator materials. The ferromagnetic shape memory alloy with a composition of Co43Ni19Ga38 undergoes a phase transformation from a B2 austenite to a L10 martensite phase at temperatures around 210 K. Alloying with a fourth element will influence the transformation temperature. To clarify the impact of a fourth element addition on the transformation temperatures material libraries covering small additions (1-10 at.%) of Fe, Cr, Cu, Si, Al, and Mn to a Co43Ni19Ga38 base material are fabricated via co-deposition magnetron sputtering. The materials libraries are analyzed with regard to their phase composition using x-ray diffraction. Additional temperature-dependent x-ray diffraction and sheet resistance measurements are performed to determine the transformation temperatures and phase composition in the thin films.