Devitrification studies of Zr–Pd and Zr–Pd–Cu metallic glasses

Abstract High temperature X-ray diffraction (HTXRD) is used to investigate the devitrification pathway for two related Zr-based metallic glasses, Zr 70 Pd 30 and Zr 70 Pd 20 Cu 10 . Both alloys have similar as-quenched structures and initially devitrify to form a meta-stable quasicrystalline phase. The HTXRD data for the Zr 70 Pd 30 alloy shows the coexistence of the quasicrystalline and the Zr 2 Pd (I4/mmm) crystalline phases over a range of 25 K. Conversely, the Zr 70 Pd 20 Cu 10 alloy shows an additional transformation of the quasicrystalline phase to a meta-stable Zr 2 (PdCu) intermetallic (Zr 2 Si type structure, I4/mcm) that polymorphically transforms to the Zr 2 Ni type structure (I4/mmm) over a very narrow temperature range.