RMC simulations of the liquid AlGe alloys

The structure of AlGe melts has been studied in a wide temperature-concentration range by Reverse Monte Carlo simulations and Voronoi-Delaunay diagrams. The experimental structure factors of the AlGe melts with ≥ 20 at.% Ge have a shoulder on high-Q side of the first peak that coincides with the one on the S(Q) of liquid Ge. There is the same shoulder on partial SGeGe(Q) that indicates the primary role of Ge in formation of the structure of binary melts near liquidus temperatures. The obtained data point out the quasi-eutectic structure of AlGe melts, which consist of atomic clusters with structure of homogeneous solution of Ge atoms in aluminium matrix and clusters with local structure like liquid Ge. The latter exist due to incomplete metallization of covalent Ge bonds during melting. An increase in temperature causes a metallization of Ge bonds resulting in disappearance of signs of pure liquid germanium's structure on experimental S(Q) and g(r) curves. Formation of the homogeneous solution with the increase in temperature promotes the process of metallization of residual covalent bonds in AlGe melts till complete conversion at ≈ 1800 K.