Paper is devoted to investigation of initiation and propagation of cracks in titanium alloys by infrared thermography study of heat generation under cyclic loading and fractography analyses of fracture surface. Two series of experiments on flat smooth specimens and flat specimens with preliminary grown fatigue crack are carried out. Spatial and time temperature evolution into crack tip is investigated, the shape and dissipative intensity at crack process zone are estimated. Based on a result of comparative analysis of the experimental data and the linear fracture mechanics equations it is shown that the spatial distribution and character of heat dissipation zone into the crack tip doesn’t correspond to the conventional models. High-speed shooting (at a frequency of 1 kHz) allowed us to determine the intensity and shape of zone of energy dissipation caused by plastic deformation at the crack tip, as well as to compare the rate of energy dissipation for different stress levels. Fractured specimens were analyzed by interferometer microscope and SEM to verify the existing models of inelastic deformation at the crack tip and to improve methods of monitoring of damage accumulation during fatigue test.

The phenomenon under study is the behaviour of a solid body placed in some fluid adjacent to an opaque horizontal plane and oscillating perpendicular to the plane. In this condition a resultant force directed from that plane and normal to it was observed to arise. This force acts like a lifting force and tends to rapidly increase when approaching the plane. Expressions for the suspension force magnitude in relation to the plane have been derived for rotary bodies of arbitrary shape, in particular, flat, concave and convex ones. This provided possibility of assessing the height of suspension and suspending behaviour of oscillating bodies that are denser than the liquid. The inferences obtained were compared with the interaction order of two pulsing or vibrating bodies studied first by C. Bjerknes and later by other researchers, including those of the Perm Scientific School of Hydrodynamics. As shown by experiments and routine observations the effect of suspension is likely to arise in a vibrating body placed in a dry loose medium, the effect causing upward motion of the body in spite of its being denser than the medium. The physical mechanism of such a phenomenon has been put under scrutiny. This mechanism, which is believed to be a peculiar form of the segregation effect, is different from that observed in fluid suspension. The cause inducing a solid body to rise to the surface is supposed to be in that the resistance force impeding displacement of the solid body into the medium insides is greater than the force directed upwards toward the free surface. A case study is described of the similar effect produced by a medium volume oscillating about the solid body. In conclusion a general principle has been formulated on the behaviour of vibrating solid and strained bodies in the vicinity of their interfaces. The research results may be used in the theoretical calculation of turbulent suspended flows, in the theory of vibrating pumps, in explanation and assessment of pipes span bulging, especially those laid on the see bottom, – they can explain also the paradoxical unsinkability of see concretions and mystical “push up“ of heavy rock boulders to the ground surface.

This paper devoted to analyzes the methodological issues of mechanical testing of filaments and fabrics, which are the reinforcing elements to create composite materials. In this paper static tensile tests techniques silica fabric CT-11-TOA and glass filaments with determination of mechanical properties develop and approved. On samples of fabric value of the maximum ultimate load is defined, the statistical analysis is carried out, the variation coefficient is counted, deformation charts are constructed. On samples of glass threads values of the maximum loading, the maximum specific loading, the elastic module and relative elongation at a gap. The diagrams of deformation carried out statistical analysis of 60 samples were obtained and the average values of the mechanical characteristics and the coefficients of variation. Tests were carried out on the electromechanical Instron 5965 testing system with use of the contactless video extensometer AVE.

The work is devoted to experimental investigation of the number of cycles to failure of aluminum alloy Д16Т in the combined loading tests at tension with torsion. The experimental results under uniaxial cyclic loading with an additional component of the constant shear stress are presented. The value of constant component of shear stress τ with respect to shear yield stress τ03 which were determined in static tests was changed from 0 to 0.7. The tests were carried out on two levels of axial stress amplitude (250 MPa and 280 MPa). The experimental data of the number of cycles to failure under different value of the additional component of the constant shear stress were obtained. It is noted that with increase of the axial stress amplitude the effect of the constant component of the shear stress is reduced.

A method of experimental research strength and dissipative properties the polyurethane is proposed. The technique of the experiment at different temperatures under conditions of dynamic cyclic compression, and tests to determine the elastic and viscous mechanical properties of polyurethane bushings made of different chemical bases. The author presents the results of researches of polyurethane bushings produced from various isocyanates: Toluene diisocyanate 4.4'-Diphenylmethane diisocyanate и 1,5-napththylene diisocyanate. The results of the dependencies viscoelastic and strength characteristics of various types of the polyurethane on temperature were obtained. A comparative analysis of the mechanical behavior of different polyurethanes according to the temperature change is carried out. In the analysis of the mechanical behavior of polyurethane bushings are built temperature chart strength, dynamic modulus of elasticity, loss factor and characteristics of changes in strength, deformation and dissipative properties with decreasing temperature operation.

Experimental research of the pressure drop in the flow of fluid in a pipe that has several local hydraulic resistance. The local hydraulic resistance were the elbow, the sudden expansion, sudden contraction, coupling and sudden turn. The experimental setup also included piezometers, variable area flowmeter, pressure and drain tanks, pump, bimetal thermometer, and a system of valves. The relative position of the elements shown in the hydraulic diagram of the experimental setup. As the liquid medium used water. Designed physical and 3D model of the fluid. Selected tetrahedral mesh model of building bulk. Choice of physical parameters correspond turbulent flow, constant density, steady-state flow with a given mass flow at the inlet section of the pipeline. Volume control method of approximation of the Navier-Stokes equations used for the numerical simulation. Simulation done in the software STAR-CCM+. Found a field of pressure distribution and velocity of the moving fluid. The possibility of an accurate determination of the coefficients local hydraulic resistance of bodies of complex geometry.