The influence of crystallization conditions of leaded tin bronze on the obtained microstructure parameters is examined in the paper. Modification of crystallization conditions was realised by varying the cooling rate of the melt with preheating of the casting molds. Quantitative regularities of the influence of the cooling rate of bronze on its phase composition are presented. Data on mechanical properties of the material under investigation are also reported in the paper. It is demonstrated that high cooling rates (casting into mold at ambient temperature) enable obtaining higher mechanical properties in comparison with low cooling rates (casting into mold heated up to 800 °С).

The literature about the mold plastering casting structures applied in alloying the casting coating by various alloys was examined. On the basis of the examined literature the main conditions are revealed, which should be observed for the implementation of the alloying process. The data on plastering structures used for the casting molds with various heat conductivity is presented. The influence of such alloying on the structure and property both of the casting surface and the properties of the finished products is shown. The data on a classical set of covering components and on the features of the elements comprising them is also provided. The conditions necessary for the casting surface alloying by the nanopowder of the casting mold covering are described. A number of cases is described when such alloying was applied and was successful. The changes of the casting surface properties are described.

In work are submitted data of casting mold coverings with nanopowders application for molding lead bronze. Influence of a structure of used protective - separating coating of a foundry core on a microstructure of castings was investigated. For experimental work following coverings (the patent No 2297300) a mix dioxide zirconium nanopowder with industrial oil, and the same structure, but already on a basis on oxide aluminum nanopowder have been chosen. It is shown that these coverings application leads to decrease in quantity of surface defects, the roughness of a cast surface decreases. At the same time penetration of particles of a powder from a foundry covering in casting doesn't occur.

In this work data on results of powders mix activation in a planetary spherical mill are presented at various modes of processing. For researches were chosen powders of aluminum oxide and copper. The ratio of initial powders mass and processing time in a spherical mill varied. Results showed that the increase in time of processing leads to powders particles crushing and introduction of firmer aluminum oxide powder particles in copper particles. Changes of powders phase structure in the activation course don't occur. Particles agglomerations at processing time till 5 minutes also it is not observed.

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