FSBEI HE Russian University of Transport (MIIT), Moscow, Russia:

V. N. Chudin, Professor of the Chair for Resistance of Materials and Structural Mechanics, Doctor of Technical Sciences, e-mail: vladimir-chudin@yandex.ru

FSBEI HE Tula State University, Tula, Russia:
V. I. Platonov, Associate Professor of the Chair for Mechanics of Plastic Shaping, Candidate of Technical Sciences, e-mail: mpf-tula@rambler.ru
P. V. Romanov, Post-Graduate Student

Relationships for calculating the technological modes of isothermal pressure welding of body cellular panels made of sheet materials are proposed. Cellular panels made of light aluminum and titanium alloys are used in aerospace engineering as load-bearing elements of body structures, wings, fairings, etc. When using such structures as fuel tanks, a reliable joining of elements is required to ensure the tightness of cavities. Compared with traditional methods of welding elements made of materials used in the aerospace industry, pressure welding can significantly reduce the complexity of manufacturing complex structures and improve their quality. Pressure welding of the workpieces included in the assembly is performed under isothermal conditions, i.e., in the solid phase. The main stages of the pressure welding technological process include: upsetting of the workpiece assembly by plastic compression, holding under pressure and relaxation (cooling). Thus, for design and calculation of this process, it is necessary to determine the maximum pressure at a given amount of upsetting, the duration of holding under pressure, and the stress relaxation time in the product material. The determination of the value of upsetting pressure was carried out by the upper-boundary method, using the energy equation of equilibrium during upsetting on the basis of the breaking field of displacement velocities and the equation of creep-plasticity during welding. Depending on the grade of the material and the temperature of forming, an expression is obtained to assess the damageability of the material of the workpieces according to the deformation or energy criteria of destruction. The results of calculating the modes of isothermal pressure welding of a body panel made of aluminum alloy AMg6 at 510 ^oC are presented and samples of products are shown.
The work is conducted within the framework of the graut NSh-2601.2020.8 for state support of the leading RF scientific schools.

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