The Phase Stability, Thermodynamics Properties and Electronic Structures of L12-Type Al3Sc and Al3Y under High Pressures
DUAN Yong-Hua1,2**, HUANG Bo1, SUN Yong1, PENG Ming-Jun1, ZHOU Sheng-Gang1
1School of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093 2Key Lab of Advance Materials in Rare and Precious and Nonferrous Metals (Ministry of Education), Kunming 650093
Abstract：The phase stability, thermodynamics properties and electronic structures of L12-Al3Sc and Al3Y compounds under pressure up to 40 GPa are investigated by using first-principles within a local density approximation. The results of formation energies show that Al3Sc is more stable than Al3Y and the stability of Al3Sc will be better with the increasing pressure. The Gibbs free energy, heat capacity, Debye temperature and thermal expansion coefficient are also investigated. The decreasing density of states at the Fermi level and the strengthening Sc/Y-d orbital hybridization with Al (s, p) under high pressure lead to the observed increase of the structural stability for L12-Al3Sc and Al3Y under pressures.
2014, Vol. 31 
