Project Scope
Amalia’s work focuses on real-time deformation behavior study of refractory high entropy alloys (RHEAs) with in situ neutron diffraction. RHEAs tend to be brittle at room temperature, making further machining processing difficult. In this study, several RHEAs compositions, which are HfNb0.5Ta0.5TiZr, HfNb0.5Ta0.5TiZr, HfNbTa0.5TiZr, HfNbTa0.5TiZr, Hf0.5NbTa0.5TiZr, Hf0.5NbTa0.5TiZr, HfNbTaTiZr, HfNbTiZr were tested at VULCAN beamline, Oak Ridge National Laboratory. All seven compositions and four out of seven compsitions possess room temperature plasticity in compression and ductility in tension, respectively. Neutron diffraction technique provides real-time evolution of lattice strain, peak broadening, and intensity, which could be correlated with load sharing of different orientation, dislocation density, and grain rotation, respectively. Lattice strain evolution reveals different load sharing behavior during compression and tension loading and different deformation behavior with different composition of RHEAs. From the peak broadening, the dislocation density can be calculated using modified Williamson-Hall plot, revealing different preferred dislocation character and slip system.
Biography
Lia Amalia is currently pursuing her PhD under Prof. Peter Liaw and Prof. Yanfei Gao in the Department of Materials Science and Engineering at the University of Tennessee, Knoxville. She holds a Bachelor’s degree in mechanical engineering from Insitut Teknologi Sepuluh Nopember, Surabaya, Indonesia in 2017 and a Master’s Degree in materials science and engineering from National Chiao Tung University, Hsinchu, Taiwan in 2020. Her current research focuses on mechanical behavior of high entropy alloys. Additionally, she is studying the real-time deformation mechanisms with in-situ neutron diffraction technique to enhance the strengthening mechanisms in high entropy alloy systems.