Continuous measurement of ultrasonic elastic wave velocities, X-ray radiography and X-ray diffraction of Zr50Cu40Al10 metallic glass at high pressure and high temperature conditions

ABSTRACT A new experimental setup to continuously and automatically measure ultrasonic elastic wave velocities, X-ray radiography, and X-ray diffraction in large volume press is developed to explore structural change of amorphous materials at in situ high pressure and high temperature conditions. A continuous measurement for Zr50Cu40Al10 metallic glass is carried out during the heating process from 304 to 1102 K under high pressure conditions of 6.8–8.6 GPa. The sample length, elastic wave velocities, and Poisson’s ratio show marked changes at 611, 745, 825, and 874 K, which are interpreted as glass transition temperature (Tg ) at 611 K, two polyamorphic structural changes at 745 and 825 K, and crystallization above 874 K, respectively. We find that the 1.2Tg temperature (733 K at ∼8 GPa), where simulations study predicted occurrence of thermal rejuvenation, corresponds to the temperature of the polyamorphic structural change (745 K) in Zr50Cu40Al10 metallic glass.