Structural organoplastics based on film adhesives

The use of VK-36RT film adhesive as a polymer bonding agent for producing structural hermetic organoplastics and VK-3 film adhesive for creating organoplastics with high shock and ballistic resistance for producing protective structures for aerotechnic purposes was considered.     

Singular perturbation analysis of dynamic fields in a thermoelastic solid with a small surface-breaking crack

An asymptotic analysis is presented for a dynamic problem of a semi-infinite isotropic thermoelastic solid with a small surface breaking crack. The exterior surface of the solid is subjected to a series of short thermal pulses. The crack surface is traction free and an ideal thermal contact is assumed across the crack. The stress intensity factor is asymptotically evaluated as a function of the crack depth and time. The effect of a boundary layer associated with the diffusive term is identified. The theoretical model is supplied with numerical simulations.     

Regularity of the free boundary in a neighborhood of a contact point in the obstacle problem

The obstacle problem for an arbitrary linear elliptic equation is considered. The regularity of the boundary of the noncoincident set is studied in a neighborhood of a contact points of the boundary of a domain. The C1-regularity of the boundary and the continuity up to contact points of the second-order derivatives of the solution are proved. Bibliography: 3 titles. Translated fromProblemy Matematicheskogo Analiza, No. 19, 1999, pp. 101–104.     

Surface impedance of a superconducting slab in the mixed state: Effect of the surface barrier

The effect of the surface barrier on the surface impedance Z of a type-II superconductor slab with a finite thickness is investigated in dc magnetic fields H ₀, which are aligned parallel or perpendicular to the slab plane. It is demonstrated that, in a perpendicular geometry, the surface resistivity ρ_s=ReZ has a maximum when the depth of penetration of the ac magnetic field is of the order of the slab thickness (size effect). For a parallel orientation of the magnetic field H ₀, the effect of the Bean-Livingston surface barrier manifests itself as a decrease in the dissipative loss and a change in the field dependence of the surface resistivity characterized by a magnetic hysteresis. It is shown for the first time that, under the conditions of persistent trapped magnetic flux, the dependence ρ_s(H ₀) is a decreasing function, which is associated, in particular, with a nontrivial suppression of the size effect.     

Aramid Textile Laminate for Shock-Resistant Elements of Aviation Constructions

Russian Journal of Applied Chemistry - Stability against a high-speed impact of textile laminates reinforced with aramid fabrics and layered metal-textile laminates composed of alternating metallic...     

An experience of using fluoropolymer materials in aviation engineering

The main grades of fluorine-containing materials, including solid and powder materials, paint-and-lacquer coatings and films, organic glasses, rubbers and sealants used in aviation engineering are described in the paper. The main operating performances are given as well.