Small-angle x-ray scattering study of phase separation in amorphous alloys during heating with use of synchrotron radiation

Some recent reports suggest that amorphous ${\mathrm{Pd}}_{46}$ ${\mathrm{Ni}}_{36}$ ${\mathrm{P}}_{18}$ and ${\mathrm{Cu}}_{50}$ ${\mathrm{Zr}}_{50}$ alloys phase separate during heating at temperatures 50–200 K below their crystallization temperatures. We have therefore obtained improved small-angle x-ray scattering (SAXS) measurements during heating of these alloys using a new experimental setup. The experimental improvements included in-the-beam heating using the very-high-intensity x-ray radiation available at the Synchrotron Radiation Laboratory, K.E.K., the use of Joule self-heating of the samples, which is made possible by the high resistivity of the amorphous phase and the use of regularly shaped, constant thickness amorphous tapes obtained by planar flow casting. No evidence of phase separation during heating prior to crystallization was obtained in glassy ${\mathrm{Pd}}_{46}$ ${\mathrm{Ni}}_{36}$ ${\mathrm{P}}_{18}$ and ${\mathrm{Cu}}_{50}$ ${\mathrm{Zr}}_{50}$ alloys.