|About this Abstract
||1st World Congress on High Entropy Alloys (HEA 2019)
||High Entropy Alloys 2019
||Grain Boundary Segregation Behavior of Mechanically-alloyed Refractory High Entropy Alloys
||Joshua A. Smeltzer, B. Chad Hornbuckle, Anit K. Giri, Christopher J. Marvel, Kristopher A. Darling, Jeffrey M. Rickman, Helen M. Chan, Martin P. Harmer
|On-Site Speaker (Planned)
||Joshua A. Smeltzer
Grain boundaries are known to affect bulk material behavior and dictate mechanical, thermal, and electrical properties. However, the role of grain boundaries in high entropy alloys is relatively unexplored as there are several open questions regarding the thermodynamic and kinetic behavior of grain boundaries in these complex microstructures. Here, a refractory alloy with equimolar Ta, W, Mo, and Nb concentrations was synthesized via high energy ball milling, and transition metal additives were strategically added to modify grain boundary structure and composition to alter thermal (e.g. grain growth) and mechanical properties (e.g. hardness). Microstructures were examined using aberration-corrected scanning transmission electron microscopy and grain boundaries were characterized via atomic-resolution imaging and energy dispersive spectroscopy. Understanding the role of grain boundary structure and composition in these materials allows for improved design of alloys with superior properties, and hence viability in extreme environment applications.