Real time synchrotron radiation studies on metallic glass (Zr_0.55Al_0.1Ni_0.05Cu_0.3)₉₉Y₁ after cold rolling

(Zr_0.55Al_0.1Ni_0.05Cu_0.3)₉₉Y₁ bulk metallic glasses heavily deformed by cold rolling were studied by X-ray diffraction (XRD) in transmission using high energy monochromatic synchrotron radiation during in situ heat treatment. No crystalline grain was detected in the cold-rolled samples. After deformation, excess free volume, ΔV_f, was measured by X-ray diffraction. In situ heating XRD results revealed that metastable crystalline phase was nucleated and grew before the formation of equilibrium CuZr₂. Further investigation showed that the metastable phase is Zr₃Al₂-type crystalline structure which is the primary crystalline phase that appears in several Zr-based metallic glasses during the thermal treatment [Plappert R, Boström M, Kühn U, Vaughan G, Yavari AR, Kvick Å. ISMANAM, Paris; 2005].