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We presented a theoretical study for the structural, mechanical, and thermophysical properties of the precipitates in 2xxx series aluminum alloy by applying the widely used density functional theory of Perdew-Burke-Ernzerhof (PBE). The results indicated that the most thermodynamically stable structure refers to the Al₃Zr phase in regardless of its different polymorphs, while the formation enthalpy of Al₅Cu₂Mg₈Si₆ is only -0.02 eV (close to zero) indicating its metastable nature. The universal anisotropy index of <i>A^U</i> follows the trend of: Al₂Cu > Al₂CuMg ≈ Al₃Zr_D0₂₂ ≈ Al₂₀Cu₂Mn₃ > Al₃Fe ≈ Al₆Mn > Al₃Zr_D0₂₃ ≈ Al₃Zr_L1₂ > Al₇Cu₂Fe > Al₃Fe₂Si. The thermal expansion coefficients (TECs) were calculated based on Quasi harmonic approximation (QHA); Al₂CuMg shows the highest linear thermal expansion coefficient (LTEC), followed by Al₃Fe, Al₂Cu, Al₃Zr_L1₂ and others, while Al₃Zr_D0₂₂ is the lowest one. The calculated data of three Al₃Zr polymorphs follow the order of L1₂ > D0₂₃ > D0₂₂, all of them show much lower LTEC than Al substance. For multi-phase aluminum alloys, when the expansion coefficient of the precipitates is quite different from the matrix, it may cause a relatively large internal stress, or even produce cracks under actual service conditions. Therefore, it is necessary to discuss the heat misfit degree during the material design. The discrepancy between <i>a</i>-Al and Al₂CuMg is the smallest, which may decrease the heat misfit degree between them and improve the thermal shock resistant behaviors.