ИСТИНА

The authors have performed a comparative study of the structures of the hypereutectic both Al87Ni8Y5 and Al90Y10 alloys obtained by rapid cooling from the liquid phase during crystallization under pressure (from 1.8 to 2.2 GPa and 7 GPa), subject to temperature changes (from 1200 to 1800°C) of the melt,through durametry, X-ray structural analysis and optical and electron microscopy. It is shown that under all the considered conditions of crystallization and the cooling rate of the melt of 1000 K/sec, there are formed crystalline phases in the alloys. Dense homogeneous structures of the alloy with dispersed primary ternary aluminides Ni and Y of variable composition (with different contents of Ni and Y) or anomalously oversaturated α-Al-solid solution and modifed eutectic, which have high hardness, are obtained.