Theoretics-directed effect of copper or aluminum content on the ductility characteristics of Al-based (Al3Ti, AlTi, AlCu, AlTiCu2) intermetallic compounds**Project supported by the National Natural Science Foundation of China (Grant Nos. 41674088, 11574254, 11272296, and 11547311), the National Basic Research Program of China (Grant No. 2011CB808201), the Fundamental Research Fund for the Central Universities, China (Grant Nos. 2682014ZT30 and 2682014ZT31), and

Abstract

First-principle simulations have been applied to investigate the effect of copper (Cu) or aluminum (Al) content on the ductility of Al3Ti, AlTi, AlCu, and AlTiCu2 alloys. The mechanical stable and elastic properties of Al-based intermetallic compounds are researched by density functional theory with the generalized gradient approximation (DFT-GGA). The calculated lattice constants are in conformity with the previous experimental and theoretical data. The deduced elastic constants show that the investigated Al3Ti, AlTi, AlCu, and AlTiCu2 structures are mechanically stable. Shear modulus, Young’s modulus, Poisson’s ratio, and the ratio B/G have also been figured out by using reckoned elastic constants. A further analysis of Young’s modulus and Poisson’s ratio reveals that the third added element copper content has significant effects on the Al–Ti-based ICs ductile character.