The results of investigation of the Cu–Zn system alloys with 10 wt.% and 30 wt.% Zn, the stacking fault energy (SFE) of which differs by a factor of 2.5, are presented. ECAP and subsequent flat rolling resulted in the refinement of the microstructure. Flat rolling with the reduction degree 95% resulted in the decrease of the concentration of nanotwins formed during ECAP. Flat rolling of ultra-fine grained (UFG) alloys leads to the strength increase and ductility decrease explained by the refinement of the microstructure and decrease in the concentration of deformation twins.

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The quality of coating on the high-silicon aluminum alloy Al-12%Si depending on the initial microstructure of the samples has been investigated. The method of microarc oxidation (MAO) has been used for coating. The quality of coating was evaluated by the thickness and microhardness of the formed layer. The initial microstructure of aluminum alloy samples was varied by distribution of silicon particles in the volume of the matrix solution. The possibility of obtaining a high-hardness protective coating on the alloy Al-12%Si by the MAO method has been shown. The influence of the alloy microstructure on the microhardness and thickness of coatings has been established. It has been shown that the deformation thermal treatment of Al-12%Si alloy samples before MAO leads to deterioration in the quality of the formed layer. A model of the influence of the silicon particles distribution on the quality of the micro-layer has been represented for explanation of the observed effect. The increase of microhardness in coatings with a greater thickness has been revealed.

The investigation studies the properties of hardened surface layers, developed with the microarc oxidation method (MAO) on ingots of a Al-Si alloy. It has been proved that properties of the developed surfaces (microhardness, thickness, porosity and corrosion properties) depend on the concentration of electrolyte components.