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The effect of variations in the composition of kaolin and basalt on the geopolymer characteristics was carried out. The drying time was 4 h for cubic samples at 40, 50 and 60 °C and 9 h for cylindrical samples at 70 and 90 °C. The best geopolymer was 4 cylinder at 90 °C, which had a compressive strength of 8.075 MPa. The density of 2 cube geopolymer ranged as 26–1.94 g/cm3 at 60 °C. Silica–alumina compounds dominated the constituent compounds of geopolymer concrete, and the phases formed were quartz, anorthite and muscovite. [ABSTRACT FROM AUTHOR]

The effect of additional rolling in longitudinal and transverse directions on the microstructure, hardness and electrical conductivity of sheet aluminum alloy AA7075 (the Russian counterpart is alloy V95) is studied. It is shown that the rolling causes inhomogeneity of the microstructure and phase composition of the alloy in longitudinal and transverse directions but does not produce anisotropy of the hardness, which amounts to 96 HV in both directions. The electrical conductivity of the alloy after the pressure treatment depends substantially on the direction of the deformation and amounts to 78.6 and 92.8 S/cm in the transverse and longitudinal directions, respectively. At the same time, the post-rolling conductivity of alloy AA7075 remains high in both directions. [ABSTRACT FROM AUTHOR]