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The special features of formation of structure in alloys Al – (20 – 50)% Si – (2 – 60)% Cu and the distribution of the alloying elements in them are studied. Metallographic analysis is made using optical and scanning electron microscopy and x-ray diffractometry. The density of the alloys is determined. The Al – Si – Cu compositions with low and steady values of the temperature coefficient of linear expansion (TCLE) α = (9.0 – 4.0) × 10 – 6 K– 1 in the range of 50 – 450°C are chosen. It is shown that the density of these alloys does not exceed 3500 kg/m3. The results of the study may be used for developing low-TCLE alloys for special fields of instrument engineering. [ABSTRACT FROM AUTHOR]

The effect of thermocycling deformation and subsequent heat treatment on the microstructure and mechanical properties of low-carbon steels 10kp, St3ps and 20 is studied in cast condition and after rolling. Metallographic analysis of the steels is performed using an optical microscope at a magnification of ×140 and ×500. The microhardness of the structural components is measured. The mechanical properties of the steels are determined in tensile tests. It is shown that after the thermocycling treatment above the temperature Ac3 all the structural components are refined. The strength of the forgings after the thermocycling treatment, quenching and low tempering increases by a factor of 1.7 – 2.4 at a satisfactory level of ductility. [ABSTRACT FROM AUTHOR]

The effect of melt hydrogen treatment on structure, morphology, and on physical and mechanical properties of hypereutectic alloy Al – 15% Si in cast and deformed conditions is studied. A melt is treated with hydrogen by different methods, i.e., with wet asbestos, in a steam atmosphere, and flushing with hydrogen prepared by alkali decomposition with aluminum. Ingots are deformed plastically by open forging and rolling. Alloy microstructure is studied by metallographic, electron microscopic, x-ray diffraction, and dilatometric analyses. Alloy density and microhardness are measured. Alloy atomic hydrogen content is studied by vacuum heating. It is shown that hydrogen treatment improves cast alloy structural parameters and deformability, raises post-deformation strength by a factor of 1.3 – 1.4, and lowers linear expansion coefficient. [ABSTRACT FROM AUTHOR]

Preserved whole blood and erythrocyte suspension in the colloid preservative "Modezhele" were studied after leukocyte filtration through newly designed leukofilter. Morphofunctional properties of erythrocytes from the filtered media remained much more potent than from the nonfiltered ones throughout 18 months of the follow-up. The filtered media exhibited good rheology and were free of microclots. It is suggested that a favourable effect of leukocyte elimination in conservation of erythrocytic media may result from inhibited activity of leukocytic enzymes, primarily, proteolytic.