Static and Dynamic Compression and Deformation Behavior of High-Entropy Transition Metal Borides
ORAL
Abstract
High-entropy transition metal boride (HEB) sample (Hf, Mo, Nb, Ta, Zr)B2 with unit cell volume V0 = 28.2 Å3 was synthesized under high-pressure and high-temperature in a large-volume Paris-Edinburgh cell at HPCAT, Argonne National Laboratory and the sample was recovered for subsequent static and dynamic compression studies. The hexagonal AlB2 structure of HEB sample was found to be stable up to 240 GPa in a diamond anvil cell study employing platinum as a pressure marker. The average nanoindentation hardness of the recovered sample is 20 GPa. The compressive yield strength or maximum differential stress of the HEB sample was measured by radial x-ray diffraction technique in a Panoramic diamond anvil cell at HPCAT to 60 GPa. The measured compressive yield strength approached 8% of the shear modulus at the highest pressure of 60 GPa. Future shock compression experiments are planned on THOR at Sandia.
**Supported by DE-NA0003916; DE-AC02-06CH11357; and DE-AC52-07NA27344SNL is managed by NTESS, LLC under contract DE-NA0003525.This work describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the work do not necessarily represent the views of the U.S. Department of Energy or the United States Government.
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Publication:Seth Iwan, Kaleb C. Burrage, Bria C. Storr, Shane A. Catledge, Yogesh K. Vohra, Rostislav Hrubiak, and Nenad Velisavljevic, "High-Pressure High-Temperature Synthesis and Thermal Equation of State of High-Entropy Transition Metal Boride", AIP Advances 11, 035107 (2021). https://doi.org/10.1063/5.0045592.
Seth Iwan, Chia-Min Lin, Christopher Perreault, Kallol Chakrabarty, Cheng-Chien Chen, Yogesh K. Vohra, Rostislav Hrubiak, Guoyin Shen, Nenad Velisavljevic, "High-Entropy Borides under Extreme Environment of Pressures and Temperatures", under review in Nature Journal Scientific Reports (2022).
