High-throughput first-principles study of physical properties of L12-Al3M particles. (June 2022)

• Record Type: Journal Article
• Authors: Fan, Touwen; Ruan, Zixiong; Hu, Te; Wang, Kai; Duan, Shiyun; Deng, Yuanxiang; Tang, Pingying; Wu, Yuanzhi
• Is Part Of: Materials today communications. Volume 31(2022)
• Publication Date: 2022-06
• Subjects: First-principles calculations -- L12 Al3M phase -- Mechanical properties -- Quasi-harmonic approximation -- Thermal conductivity; Materials science -- Periodicals; 620.11
• DOI: 10.1016/j.mtcomm.2022.103748
• Languages: English
• ISSNs: 2352-4928

Abstract

Abstract: The mechanical, thermal and electrical properties of L12 -Al3 M (M=RE (Sc, Y, La-Lu), Li, Na, Ca, Fe and Cu) in Al based alloys at various temperatures and pressures have been investigated by combining first-principles calculations with quasi-harmonic approximation. The results show that the lattice constant, lattice mismatch, and formation enthalpy of L12 -Al3 M compounds are closely related to the radius of M atoms and electrons transferred from M to Al. Al3 La presents the largest strengthening effect, while Al3 Sc shows the most stability. The elastic parameters of Al3 M compounds increased linearly with the increase of pressure, but slightly decreased with temperature, while Poissson's ratio ν and Pugh's ratio B/G maintain the characteristic of brittleness. The calculated electrical conductivity of L12 -Al3 M is nearly unchanged, whereas the thermal conductivity is increased with the increase of temperature. The lower values of Seebeck coefficient and merit ZT clearly indicate that these L12 -Al3 M compounds show metallic bond feature and are not suitable for thermoelectric devices. Finally, the thermal conductivities (TCs) of Al alloys containing L12 -Al3 M as functional of compound concentration and temperature are obtained based on the Maxwell model. These results are helpful for designing high performance heat-resistance Al alloys. Graphical Abstract: ga1 Highlights: The lattice constant, lattice mismatch, and formation enthalpy of L12 Al3 M compounds are closely related to the radius of M atoms and electrons transferred from M to Al. All the elastic parameters of Al3 M compounds are increased nearly linearly with the increase of pressure, but are decreased with temperature, whereas the Poissson's ratio ν, B/G can hardly be changed and maintained the characteristic of brittleness. The calculated electrical and thermal conductivities of L12 Al3 M are nearly unchanged and increased with the increase of temperature, respectively, which is in good agreement with the Wiedemann–Franz law. The lower values of Seebeck coefficient and merit ZT clearly indicates that these L12 Al3 M compounds are not suitable for the thermoelectric devices. The influence of compounds on the thermal conductivity of Al alloys are increased with increasing the temperature, while are decreased with the increase of volume fraction of second phase L12 Al3 M.