title: The effects of alloying elements Al and In on Ni-Mn-Ga shape memory alloys, from first principles.
abstract: The electronic structures and formation energies of the Ni(9)Mn(4)Ga(3-x)Al(x) and Ni(9)Mn(4)Ga(3-x)In(x) alloys have been investigated using the first-principles pseudopotential plane-wave method based on density functional theory. The results show that both the austenite and martensite phases of Ni(9)Mn(4)Ga(3) alloy are stabilized by Al alloying, while they become unstable with In alloying. According to the partial density of states and structural energy analysis, different effects of Al and In alloying on the phase stability are mainly attributed to their chemical effects. The formation energy difference between the austenite and martensite phases decreases with Al or In alloying, correlating with the experimentally reported changes in martensitic transformation temperature. The shape factor plays an important role in the decrease of the formation energy difference.
authors.affiliation: School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, People's Republic of China. Beijing Key Laboratory for Advanced Functional Materials and Thin Film Technology, Beijing University of Aeronautics and Astronautics, Beijing 100083, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Jia-Xiang
authors.initials: JX
authors.lastname: Shang
authors.forename: Hui-Bin
authors.initials: HB
authors.lastname: Xu