Nanocrystallization of the Fd<SUP>3¯</SUP>m Ti<SUB>2</SUB>Ni-Type Phase in Hf-Based Metallic Glasses

Three ternary and four quaternary hafnium-based alloys have been rapidly solidified, and the devitrification of the resultant metallic glasses has been studied to evaluate the influence of composition on the products. The formation of metastable and stable Fd3¯m (Pearson symbol cF96) Ti<SUB>2</SUB>Ni was evident whenever the alloy composition in the stable equilibrium diagrams showed this phase. The replacement of nickel by iron led to the appearance of this phase in preference to the icosahedral quasicrystal. Several common features of the amorphous alloys that form either nanoscale icosahedral or cF96 Ti<SUB>2</SUB>Ni-type phases on devitrification are discussed and summarized