Quantitative Phase Analysis of Aluminium-Lithium Alloys

Abstract:

A quantitative approach to the determination of the phase composition in the Al-Mg (Cu)-Li alloys has been developed on the basis of the balance equations of chemical and phase compositions as well as the lattice parameter measurement of the α solid solution. It is shown that, for the Al-Mg (Cu)-Li alloys, the ratio between the fractions of the δ' (Al₃Li) and S₁ (T₁) phases is determined by the ratio between the molar fractions of Li and Mg (Cu). By means of this technique it is shown that in Al-Cu-Li alloys the proportion of δ'-phase is much higher than ternary T₁-phase, and the proportion of δ'-phase and a ternary phase (S₁) are approximately equal in alloys of Al-Mg-Li system. The equations for the calculation of the contents of the S₁ (Al₂MgLi), T₁ (Al₂CuLi) and δ' (Al₃Li) phases in the 1420, 1424, 5090 alloys (Al-Mg-Li alloys) and in the 1440, 1441, 1450, 1460, 1461, 1464, 1469, 2050, 2090, 2091, 2094, 2098, 2099, 2195, 2198, 2199, 2297, 8090 (alloys (Al-Cu-Li alloys) are given.

• Periodical: Materials Science Forum (Volume 877)
• Pages: 258-263
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.877.258
• Online since: November 2016
• Authors: Sergey Betsofen*, Vladislav Antipov, Maxim Knyazev, Margarita Dolgova
• Keywords: Al-Li Alloys, Phase Composition, Texture, δ'-Phase

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