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The authors investigated the effect of mechanical activation and self-propagating high-temperature synthesis (SHS) on the phase composition of composite materials of Al-TiO2-B system. It has been shown that with increasing the duration of mechanical activation of initial powders the amount of crystalline boron-containing phases in the mixture increases. X-ray diffraction analysis of powder mixtures after SHS allows making conclusion about necessity of activation for at least 45 min to obtain a target compounds. Experimental results allow reasonably choosing the modes of mechanical activation for production of aluminium matrix composites with specified composition and controllable properties.

Aluminum protectors are used in cathodic systems for protecting metal structures from electrochemical corrosion. The materials of the article are devoted to the selection of elements for alloying aluminum, based on the analysis of physicochemical, technological and electrochemical characteristics of the alloy base and elements of the periodic system named after D.I. Mendeleev. Zn, Mg, Mn, Ti and Zr were selected as the main alloying components by the tendency of elements to alloy formation and to obtain a homogeneous structure, taking into account their effect on the anodic activity and resistivity of oxides on the metal surface. The obtained research results are in good agreement with the well-known international standards for the chemical compositions of aluminum tread alloys, for which magnesium, zinc, and manganese are present as the main alloying components. For experimental studies, Mg, Zn, Mn were chosen as alloying additives, and Si, Fe as impurities. The optimal the concentration range of the aluminum alloy will be as follows: for zinc, 3.6-5.4; for magnesium, 0.55-1.05; for manganese 0-0.3. The content of Si and Fe in the alloy is limited to 0.06 and 0.01%, respectively. The maximum value of the CUE - 75.78%.

A thermodynamic assessment of the effect of alloying elements (Si, Mg, Cu, Ti) on phase formation processes during the production and liquid-phase processing of cast aluminum matrix composite materials with exogenous reinforcement (Al–SiC, Al–B4C) was carried out. It was shown that without suppressing Al–Si–C and Al4C3 carbide formation in the range of carbon concentrations from 0 to 4.5 wt.%, the equilibrium phase composition of Al–SiC composites in the solid state at 423 to 575 °C lies in the (Al) + Si + Al4SiC4 three-phase region, and the Al4SiC4 ternary carbide is replaced by the Al8SiC7 compound at a temperature below 423 °C. SiC and B4C phases in Al–SiC–Cu and Al–B4C–Cu systems are stable in the entire crystallization range and do not interact with aluminum or copper. In the Al–SiC–Mg system, the crystallization of composites containing more than 0.58 wt.% magnesium ends in the (Al) + Al3Mg2 + SiC + Mg2Si four-phase region. In the Al–SiC–Ti system, the end of crystallization is observed in the (Al) + Al3Ti + SiC three-phase region. In the Al–B4C system, once Al4C3 phase formation is suppressed, aluminum borides are formed with a deviation from the concentrations of elements providing 10 vol.% B4C towards boron increase and free carbon is formed with a deviation towards boron decrease. Under equilibrium conditions, Al–B4C–Si system crystallization ends in the (Al) + B4C + AlB12 + Al8SiC7 four-phase region (at a silicon content of up to 0.67 wt.%, and in the (Al) + Si + AlB12 + Al8SiC7 region at a higher silicon content. In the Al–B4C–Ti system, crystallization ends in the (Al) + TiB2 + B4C three-phase region at a titanium content of less than 0.42 wt.%.