Multiscale Microstructural Investigation of Additively Manufactured Tungsten Heavy Alloys
About the Event
Tungsten heavy alloys (WHAs) are two-phase metallic composites used in applications like aircraft engines, radiation shields, and nuclear fusion reactors because of their improved room temperature ductility and machinability compared to pure tungsten.
Additive manufacturing (AM) allows engineering microstructures by tuning processing parameters and fabricating components with complex geometries. Previous research on AM WHAs primarily focused on optimizing processing conditions to produce high density parts with minimal defects. However, microstructure design is necessary to optimize thermal and mechanical behavior of AM WHAs for their various applications.
This study lays the groundwork towards microstructure design through multiscale characterization by examining the rapid solidification microstructure of AM WHAs at the nanoscale. A 90W-7Ni-3Fe WHA was fabricated using laser powder bed fusion (LPBF) and its microstructure was thoroughly investigated using transmission electron microscopy (TEM), to complement scanning electron microscopy (SEM) observations. While SEM revealed microscale inhomogeneity as reported in previous research, TEM analysis provided nanoscale insight into phase distribution, dislocation structures, and precipitate morphology. These nanoscale findings, not previously observed by SEM, provide a foundation to understand the microstructure-mechanical behavior relationship in AM WHAs, and link their processing, microstructure, and performance for real-world applications.
About the Speaker
Anugrahaprada Mukundan is a Ph.D. student advised by Prof. Mitsu Murayama in the Materials Science and Engineering department at Virginia Tech. She received her Bachelor’s degree in Mechanical Engineering from National Institute of Technology, Surat, India in 2021 and her Master’s in Materials Science and Engineering from the University of Illinois at Urbana-Champaign in 2023. Her research focuses on understanding the relationship between the microstructure and properties of additively manufactured or 3D printed alloys. She performs materials characterization, particularly SEM and TEM, as a part of her research.