Zr-based Metallic Glass
Oxidation behavior of Zr-based metallic glasses has been studied at temperatures below glass temperature (Tg), crystallization temperature (Tx), and between Tg and Tx in air atmosphere. This behavior affects significantly on the structural stability of the amorphous alloys. At those specified temperatures, the oxidation behavior and crystallization of the amorphous Zr-based alloy could be observed clearly. Mechanism of the oxide growth was be studied by analyzing x-ray diffraction patterns for isothermal oxidation with variation of oxidation time. Generally, the non-crystalline oxide was formed after the crystalline oxide. This implies that the crystallization of the amorphous Zr-based alloys is formed after oxidation.
Fracture surface of Zr-based metallic glass
X-ray diffraction patterns of oxidized Zr-based metallic glass in air at 390oC with variation of time exposure show the micromechanism of oxidation
(a). Intial, (b). 10 min., (c). 15 min., (d). 20 mim., (e). 60 min.,
(f). 90 min., (g). 120 min., (h). 180 min.
Microstructure of oxidized Zr-based metallic glass observed using SEM and TEM