Experimental and DFT characterization of η′ nano-phase and its interfaces in Al Zn Mg Cu alloys

By F. Cao, J. Zheng, Yong-zheng Jiang, Bin Chen, Yiren Wang, Tao Hu. Acta Materialia, 2019

154 citations recorded by the source corpus.

Abstract The structures and energetics of η′ nano-phase and its interfaces in a peak-aged Al Zn Mg Cu alloy were thoroughly investigated, using the combination of aberration corrected HAADF-STEM imaging and first-principles calculations. The most feasible atomic structure of η′, along with the solute substitution in η′, were calculated and compared with the atom resolution Z-contrast images. The interface phase diagram of η′/Al was constructed as a function of the excess chemical potential of Zn, to determine the equilibrium interface structures. Solute segregation to these interfaces was further calculated, and the results were adopted to interpret the experimental Z-contrast images. Finally, all the bulk and interface results were integrated to predict the solute partition in the matrix and further its potential impacts on interface properties, and based on which, a new strategy was proposed for future optimal design of Al Zn Mg Cu alloys.

Subfields: Aerospace Engineering, Materials Chemistry, Mechanical Engineering

View Paper: https://www.semanticscholar.org/paper/f093d71ee10dce6249497bf0ab27f505f4b94a0f