Проведен анализ современных методов внешних физических воздействий на алюминиевые сплавы в процессе литья и добавления в них упрочняющих элементов: механического перемешивания, воздействия электромагнитными полями, обработку ультразвуком, вибрации. Выделены преимущества и ограничения этих методов. Обсуждаются процессы, происходящие во время применения воздействий, их конечное влияние на эксплуатационные свойства получаемых сплавов. Приведены схемы технологических установок, с помощью которых реализуются воздействия, и собственный опыт обработки легких сплавов внешними физическими полями.

Ultrasonic processing in the cavitation mode is used to produce the composite materials based on the metal matrix and reinforcing particles of micro-and nano-sizes. In such a case, the deagglomeration of aggregates and the uniform distribution of particles are the expected effects. Although the particles can not only fragment in the acoustic field, they also can coagulate, coarsen and precipitate. In this paper, a theoretical study of processes of deagglomeration and coagulation of particles in the liquid metal under ultrasonic treatment is made. The influence of various parameters of ultrasound and dispersion medium on the dynamics of particles in the acoustic field is considered on the basis of the proposed mathematical model. The criterion of leading process (coagulation or deagglomeration) has been proposed. The calculated results are compared with the experimental ones known from the scientific literature.

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In the manuscript process of crystallization of metals at ultrasonic influence is considered. The known models of crystallization under the influence of ultrasound are investigated. By means of calculations influence of parameters of ultrasonic influence and characteristics of crystals of metal on the received structure of alloy is established. The corresponding mathematical model of ultrasonic crushing of particles and their agglomerates in metal fusion is offered. It is determined the threshold mode of ultrasonic influence on fusion at which almost monodisperse distribution of particles by the sizes is reached.