Annotation: The comparison has been made of mechanical characteristics based on yield strength values of prospective aluminum alloys and steels with the stresses arising in pipeline parts. The conclusions have been drawn about the principal feasibility of manufacturing the pipelines of given materials and replacing the steels with the high-strength aluminum alloys for majority of the parts.

Annotation: The paper considers the TZS-U design developed by Yuzhnoye SDO specialists for windward part of reusable spacecraft with external metal three-layer panel, U-like joint and tiled thermal protection, in which the problem is solved of compensation of thermal expansions and sealing of gaps; for optimization of structural mass. The specially created dispersion-hardened powder alloy based on nichrome and aluminum with yttrium dioxide with decreased specific mass of 7500 kg/m3 and lighter felt of MKRF brand are used , and honeycomb filler of three-layer panel is replaced by the filler with square cell.

Annotation: This article considers the practical data on parts (specimens) manufacturing from powder metal material 316L using the innovative method of selective laser melting; the comparative study of the structure and physical and mechanical properties of 316L material, the combined influence of heat treatment and specimen orientation relative to the arrangement plate on the physical and mechanical properties and structure of specimens made of 316L alloy. Results are presented of the following: comparative study of the physical and mechanical properties and structure of specimens, manufactured using the selective laser melting technologies with horizontal and vertical placement relative to the arrangement plate; dependence of the ultimate strength and unit elongation on the annealing temperature. The possibility and suitability of the selective laser melting technology to manufacture parts and space-rocket hardware are evaluated. Experimental study of the specimens heat treatment conditions after selective laser melting enabled the definition of the optimal condition for the 316L alloy and have shown that heat treatment of the manufactured specimens under the heating at 1230 °С with the subsequent tempering at the temperature of 510 °С gives the homogeneous structure to the material of specimens made of alloy 316L, its dendritic structure, inherent in the specimen material in its initial condition, disappears after selective laser melting. Results of the mechanical tests of the obtained specimens have shown that the technology of selective laser melting provides development of products made of powder metal material 316L with optimal complex of physical and mechanical properties. It is shown that transition to the selective laser melting technology will enable production of the aerospace products, in particular geometrically-complex parts made of powder metal material 316L, in one technological cycle, excluding cutting, punching, refinement, cropping, welding, manufacturing of special tools or stamps

Annotation: Gasars is a new type of porous cast materials manufactured on the basis of metals and their alloys, some types of ceramics. The basis of the process is gas-eutectic conversion in the system metal-hydrogen. The process of investigation and creation of gasars was commenced in 1979 in the National Metallurgical Academy of Ukraine and is currently continued in Ukraine, the USA, China, Japan, South Korea, Poland and others. The gasars production technological process consists in melting the specified material (metal, alloy, ceramics) in hydrogen (or other active gas) atmosphere at a certain pressure. After the melt is saturated with active gas to a certain concentration, the crystallization process begins at which the pore formation process is launched. As the pores growth occurs perpendicular to crystallization front, the orientation of heat withdrawal influences pores location. So, for example, to obtain radial porosity, radial heat withdrawal is required. To obtain various structures, along with directed crystallization process, the pressure in crystallization chamber is an important factor, which drives the gasar morphology. The porous structure of gasars is diverse, there are the gasars with longitudinal, cylindrical, spherical, conical pores. It is possible to alternate the porosity layers and monolithic metal layers. The dimensions of gasars pores are in the limits from 10 μm to 10 mm at total porosity from 7 to 55 (75%). However, there is a possibility to obtain the pores with smaller diameter. The mechanical properties of gasars have a number of advantages as compared with conventional porous materials produced by different methods. Subsequent processing of the gasars does not differ from analogous non-porous materials, which is also an advantage over conventional porous materials. And in case when the diameter of pores is less than 50 μm, the exceedance of mechanical properties of gasars as compared with monolithic materials of the same chemical composition is observed. This is caused by the fact that the pores were formed during crystallization and at the action of pressure on a gasar, local hardening occurs. At present, the gasars have already found application as light and strong structural materials, filters, heat exchangers, dampers, slide bearings, catalyst elements, friction materials, etc. The use of gasars in space hardware will help to considerably reduce the mass of launch vehicle structural elements without worsening strength properties. The possibility of welding and soldering the gasars allows finding their application in the structure of propellant systems, compressed gas and propellants supply systems, creating filtering elements based on the gasars, including propellant spraying and mixing systems.

Annotation: The main task of the radiotransparent radome design is to develop a structure that reliably protects the aircraft components, sensitive instrumentation of the guidance system from incoming air flow and heating in all phases of operation, meeting all the requirements of minimum weight, allowable temperature under the radome, strength, centre of mass and radio characteristics. Development of the radome solves the complex task of coupling and optimization of the geometric aspects of design with physical-mechanical, radio and thermal properties of materials. The article dwells on the aspects of development of the radiotransparent radomes depending on the aircraft flight speed; basic requirements for the selection of outside perimeter configuration; structural materials, providing the required radio properties in combination with minimum mass and necessary strength, acceptable temperature inside the fairing. Yuzhnoye-developed radome for the up to 5 M aircraft was considered, consisting of ogive shell made of АФ-10ПО fiberglass, heat-resistant tip and structural ring made of aluminum alloy. Methods of thermal and strength analyses of the shell are considered, results of calculations confirming the fitness for work of the structure are presented. Options of configuration with ceramic shells and methods of their coupling with rings are presented for the aircraft that reaches up to 5 M speed. Basic principles of radiotransparent radomes development and aspects of ceramic shells coupling with structural rings are considered, as well as the results of strength analyses and thermal calculations that ensure the performance of the structure and equipment in the area under the radome.

Annotation: Explosive bolts are widely used as actuating devices in the spacecraft separation systems. Explosive bolt body is divided into parts as a result of engagement of the pyromixture placed inside. Activated explosive bolts have negative mechanical effect on the interface elements and sensitive electronic devices installed nearby owing to explosive behavior of the pyromixture combustion, generating shock front with high pressure and velocities, impacts and collisions of the structural units. Cumulative effect of the above factors on the separated objects is called pyroshock. For separation systems with increased requirements to external actions and cleanliness, authors developed a shear explosive bolt or pyrobolt, divided into parts, cutting the body walls in segments, which are set in motion by action of the pressure of gases, released as a result of pyrocartridge activation. The basic sources of pyroshock for these shear explosive bolts with segments are: combustion of pyromixture, internal impacts of structural units against the bolt body; cutting of body wall in segments, release of preliminary deformed interface after activation. Structural solutions are presented to reduce the pyroshock per each of the components. Vibration impulsive loading during pyromixture combustion is reduced by optimization of explosive quantity, finding its minimum to provide the reliable activation of the device. To reduce the impact on the explosive bolt elements and shock front interface the rubber gasket is installed in the path of shock wave distribution, partially disseminating and absorbing its kinetic energy. Damper, made of easily deformable aluminum alloy, is also installed to decrease the internal impact of the rod against the explosive bolt body. Functional testing of the device, using the pendulum suspension and measuring separation speed and vibration impulsive loading, showed that body parts of the shear explosive bolt with segments are separated without significant impact loads and discharge of high-temperature gases and debris, providing reliable separation of compartments and units without damaging the sensitive equipment. Obtained values of the mechanical momentum, I = 0,4÷0,7 N•s and shock load spectrum – g-load 1950 g at the frequency range up to 5000 Hz, meet the up-to-date requirements to pyrotechnical devices.