International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The study determines the effect of gas-bubbling refining time on porosity and mechanical properties of low-pressure AlSi7Mg alloy castings under industrial conditions. Refining was performed with an NH2 mixture (90% N + 10% H2) for 5.0–9.0 min. Porosity, density index, HB hardness, tensile strength Rm, 0.2% proof stress Rp0.2 and elongation A were evaluated. The optimum refining time was 7 min, giving minimum porosity and mechanical properties meeting customer requirements. Longer refining increased porosity and reduced selected mechanical properties.

The work is devoted to the study of evolution of flaws in aluminium alloys of Al-Zn-Mg-Cu, Al-Cu-Mg-Мn alloying systems and to the determination of their connection with structural factors of the material such as the size and composition of intermetallic phases conditioned by heat treatment tempers, and also to the study of the effect of big number of physical factors on the long-term behaviour of structural elements of aluminium alloys, and to the determination of the rate of formation of corrosion damages in structural elements of the aircraft wing

The primary role of the space materials science is to ensure the long-term trouble-free operation of materials and elements of equipment in a space environment. The achievements of space materials science are a solid foundation for solving these tasks. In this paper we present the first part of the analysis of some different aspects of the space environment and their effect on the properties of materials (such as high vacuum conditions, own external atmosphere, collisions with particles, solar electromagnetic radiation, solar wind, penetrating corpuscular radiation) which are located or are mounted on the body of the International Space Station. But there are still problems such as the electrification of satellites, the work of materials in the atmosphere of heavy nuclei, the surface potential of the International Space Station, etc., which will be the subject of our next, second part of this study.