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Abstract.To accommodate for a growing number of requests by our user community an insitu heater has been commissioned for the X-ray absorption spectroscopy (XAS) beamline 12-ID at the Australian Synchrotron. Here, we present an in-situ method for calibrating the temperature of the heating stage based on an anharmonic, correlated Einstein model. Specifically, we show that a temperature-dependant study of a bulk metallic foil (7.5 µm Cu) can be used to accurately calibrate the temperature of the heater. We also present the temperature-dependant coordination number, bond length, Debye-Waller factor, and third order cumulant to the bond length distribution function of the material from 18K to 1074K. At the higher temperatures we find that the atomic structure is comparable to that of an amorphous or liquid material indicating a gradual transition from crystalline to disordered atomic structure.

Sheets of a Mg60Cu29Gd11 alloy were produced by twin roll casting with all operational variables, except roll speed, being kept constant. As a function of the roll speed, the structure of the as-cast sheet changed from being crystalline to fully amorphous and then back to crystalline. Through careful selection of the casting speed that is suitable for the selected alloy system and with which the exit temperature of the sheet remains within the supercooled liquid region, a malleable sheet with no surface defects is produced. This work shows that twin roll sheet casting is a viable process for the production of magnesium-based bulk amorphous sheet in a continuous manner and on an industrial scale.