Bulk Metallic Glass Research

Metallic glasses exhibit very high strength and intrinsically low density due to their “liquid-like” atomic structure.  This seemingly “random” atomic ordering has been historically difficult to measure, but recent work has characterized it in simple systems using advanced X-ray sources and first principles simulations [1-3].

Previous work in the High Strain Rate Lab with a bulk metallic glass indicated a shock induced transition to a high-pressure phase with a higher bulk modulus [4].  High pressure studies performed quasi-statically with a diamond anvil cell on a binary Ce-Al metallic glass showed pressure-induced polyamorphism into a higher density amorphous structure at pressures above ~1 GPa [5] and then crystallization into a unique phase at ~25 GPa [6].

This work focuses on characterizing the shock compression induced atomic structural changes in Ce3Al metallic glass.  Shock compression is accomplished using the 3J Nd:YAG pulse laser in the High Strain Rate Lab and the 50 J OMEGA laser at the Laboratory for Laser Energetics in Rochester, NY.  Characterization of recovered samples is performed using the National Synchrotron Light Source (I & II) at Brookhaven National Lab.  The results of this work will advance our fundamental understanding of pressure-induced phase changes in metallic glasses.

Figure 1: Cross-Sectional Schematic of the Georgia Tech HSRL Nd:YAG pulsed laser shock setup

Figure 2: Schematic illustration of the side (a) and top (b) view of the sample stack used in the recovery tube (c) for OMEGA laser experiments

[1] Miracle, D. B., “A structural model for metallic glasses,” Nature Materials, vol. 3, pp. 697-702, Oct. 2004.

[2] Miracle, D. B., “A Physical Model for Metallic Glass Structures: An Introduction and Update,” JOM, vol. 64, pp. 846-855, July 2012.

[3] Ma, E., “Tuning order in disorder,” Nature Materials, vol. 14, pp. 547-552, June 2015.

[4] Martin, M., T. Sekine, T. Kobayashi, L. Kecskes, N. N. Thadhani, “High-Pressure Equation of State of a Zirconium-Based Bulk Metallic Glass,” Metallurgical and Materials Transactions A, vol. 38, pp. 2689-2696, Nov. 2007.

[5] Zeng, Q., et. al., “Origin of pressure-induced polyamorphism in Ce75Al25 metallic glass,” Physical review letters, vol. 104, no. 10, pp. 105702, 2010.

[6] Zeng, Q., et. al., “Long-range topological order in metallic glass,” Science, vol. 332, no. 6036, pp. 1404-1406, 2011.