About Replacement of Nickel as Amorphization Element for Fabrication of Ultra-Rapidly Solidified Ti-Zr Alloys

Amorphous alloys based on titaniumzirconium seem to be perfect candidates as metallic biomaterials. However, the most successful results are based on alloying elements such as nickel, which is responsible for allergic effects to a considerable percent of human population. Therefore the elimination of nickel and addition of other alloying elements with amorphization effect, such as gallium and/or hafnium, have been considered for this paper. Starting from already classic Ti-Zr-Cu-Ni-Si-Sn composition, samples with additions of gallium and hafnium at the expense of nickel have been fabricated by mean of ultra-rapid cooling, using copper mold suction casting. The structures of the as-cast rods have been investigated using X-rays diffraction and electron microscopy.