Open AccessEffects of the doping of Al and O interstitial atoms on thermodynamic properties of -Al2O3:first-principles calculations
Author(s) -
Ao Huang,
Zhipeng Lu,
Meng Zhou,
Xianming Zhou,
Tao Ying-Qi,
Peng Sun,
Juntao Zhang,
Tingbo Zhang
Publication year - 2017
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.66.016103
Subject(s) - materials science , thermite , atom (system on chip) , thermodynamics , oxide , doping , bulk modulus , thermal expansion , work (physics) , aluminium , metallurgy , composite material , physics , optoelectronics , computer science , embedded system
Al particles are widely used as a metal reductant in the thermite, and a native Al2O3 film always forms on the particle surface as a passivating oxide shell. The diffusions of Al and O atom through the oxide shell will influence the structure and thermodynamic properties of Al2O3, and thus the ignition process of the thermite. In this work, the thermodynamics properties of -Al2O3, -Al2O3 doped by Al interstitial atom and -Al2O3 doped by O interstitial atom under high pressure and temperature are comparatively investigated by the first-principles calculations based on density-functional theory and quasi-harhmonic Debye model. The effects of the doping of Al and O interstitial atoms on the thermodynamic properties of -Al2O3 are discussed. The results indicate that the doping of the Al and O interstitial atoms will reduce the bulk modulus, and increase the volume thermal expansion coefficient and constant volume heat capacity of -Al2O3. Therefore, the diffusions of Al and O atom will make the oxide shell more ductile, and adverse to the spallation during the ignition of Al particles.