Structural Features of Ingots Made of Al-Cu-Li System Alloys Depending on its Chemical Composition

The purpose of the research was to examine the microstructure and phase composition of ingots made of Al-Cu-Li-Mg system model alloys. The study tested the influence of the main doping elements on the phase composition and ingot structure in casted and homogenized states. We defined temperature intervals of phase transformations and chose homogenizing temperature by means of differential scanning calorimetry. As a result, we made polythermal and isothermal sections of thermodynamic diagrams of investigated alloys using Thermo-Calc program. The alloys under consideration are in α + δ(AlLi) + T₁(Al₂CuLi) + S(Al₂CuMg) phase area.

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