Exploration of D022-Type Al3TM(TM = Sc, Ti, V, Zr, Nb, Hf, Ta): Elastic Anisotropy, Electronic Structures, Work Function and Experimental Design

Guowei Zhang; Fenger Sun; Heping Liu; Xiaoyan Ren; Hong Xu; Mingjie Wang; Yizheng Fu

doi:10.3390/ma14092206

Exploration of D0₂₂-Type Al₃TM(TM = Sc, Ti, V, Zr, Nb, Hf, Ta): Elastic Anisotropy, Electronic Structures, Work Function and Experimental Design

Materials (Basel). 2021 Apr 25;14(9):2206. doi: 10.3390/ma14092206.

Authors

Guowei Zhang¹, Fenger Sun¹, Heping Liu¹, Xiaoyan Ren², Hong Xu¹, Mingjie Wang¹, Yizheng Fu¹

Affiliations

¹ School of Material Science and Engineering, North University of China, Taiyuan 030051, China.
² Department of Mechanical Engineering, Taiyuan Institute of Technology, Taiyuan 030008, China.

Abstract

The structural properties, elastic anisotropy, electronic structures and work function of D0₂₂-type Al₃TM (TM = Sc, Ti, V, Y, Zr, Nb, La, Hf, Ta) are studied using the first-principles calculations. The results indicate that the obtained formation enthalpy and cohesive energy of these compounds are in accordance with the other calculated values. It is found that the Al₃Zr is the most thermodynamic stable compound. The mechanical property indexes, such as elastic constants, bulk modulus, shear modulus, Young's modulus, Poisson's ratio, and Vickers hardness are systematically explored. Moreover, the calculated universal anisotropic index, percent anisotropy and shear anisotropic factors of D0₂₂-type Al₃TM are analyzed carefully. It demonstrates that the shear modulus anisotropy of Al₃La is the strongest, while that of Al₃Ta is the weakest. In particular, the density of states at Fermi level is not zero, suggesting that these phases have metal properties and electrical conductivity. More importantly, the mechanisms of correlation between hardness and Young's modulus are further explained by the work function. Finally, the experimental design proves that D0₂₂-Al₃Ta has an excellent strengthening effect.

Keywords: experimental design; mechanical anisotropy; orientation relationship; structural properties; trialuminides; work function.