Aluminum alloys in a rapidly quenched state are studied by four technological methods, namely, fabricating foils and wire with unique properties, fabricating granulated alloys, surface strengthening and alloying articles by a laser or an electron beam treatment, and realizing superplasticity. In rapid quenching of alloys, crystallization occurs with cooling the melt at a rate of at least 103 --104 K/sec. Such cooling can be realized in practice by several methods, for example, by drop crystallization on a rotating heat-conducting substrate, spraying of the melt in a cooling medium, quenching a thin foil on cooled rolls in liquid rolling, or melting a thin surface zone of a quite massive part. The present paper describes a study of flakes of aluminum alloys obtained by the method of drop crystallization.Rapid quenching makes it possible to increase the solidstate dissolution of elements above the equilibrium value, diminish the inhomogeneity of the composition of the alloy, attain a finer grain size, finer ceils, phases and dendrites, and improve the mechanical and physical properties [ 1 -7].Rapid cooling of the melt creates a nonequilibrium state in the alloy, which should affect substantially its behavior in subsequent heat, deformation, and other actions.We studied flakes about 100 p.m thick which were prepared from D16 aluminum alloy (4.2% Cu, 1.4% Mg, 0.8% Mn, 0.4% Fe, 0.3% Si, 0.1% Zn, about 0.05% Ni and about 0.05% Ti) by the method of drop crystallization on a rotating metallic substrate in the shape of a disk. The initial composition was heated to 700 and 800~ The cooling rate in crystallization was 104 ~ The flakes had various shapes. Their size along the direction of the rotation of the substrate was greater than that along the disk radius. The mean sizes of the flakes in these directions were 12 and 7 mm, respectively.It has been shown ( Fig. 1) that flakes of alloy DI6 fabricated using a melt heated to temperature t m = 700~ has a predominant grain size dg= 18 -40 p.m, and at t m = 800~ dg= 50 -73 p.m. Taking into account that in the center of an ingot 360 mm in diameter cast by conventional technology the grain size d e = 375 + 35 p.m, we see that rapid crystallization diminishes of the grain size by a factor of 6 -10. Figure 2 shows the dendritic structure of the flake surfaces. It can be seen (Fig. 2a) that depending on the direction of growth in the crystallization process adjacent dendrites are cut on the surface of the microscopic specimen over different section planes characterized by specific structural features
