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Aluminum-fiber-reinforced plastics (GLARE) are promising aviation materials with increased characteristics of specific stiffness and strength, fatigue strength, impact resistance, and residual strength after impact. Nowadays, GLARE are used for making elements of the fuselage of the long-haul passenger aircraft Airbus A380, as well as some other elements of aircraft structures. The results of experimental studies of eigenfrequencies and damping coefficients of three-layer beams made with face sheets of five-layer GLARE and with a core made of polyimide foam are presented. The tests were performed using the method of free bending vibrations of cantilever samples. The dynamic parameters of the three-layer beams were calculated based on the analysis of amplitude-frequency characteristics obtained by the fast Fourier transform method. Mechanical characteristics of GLARE and filler samples are preliminary determined in static and dynamic tests. The damping factor of the core is determined by the dynamic mechanical analysis method. The core shear modulus is determined by measuring the flexural rigidity of manufactured three-layer beams in a quasi-static three-point bending test. Based on a comparison of the design data and the results of the experiments, it is shown that in dynamic tests, the flexural rigidity of three-layer specimens is reduced in comparison with the estimated values, which may be due to the peculiarities of changing the characteristics of the foam core under dynamic loading. The value of the damping factor of GLARE samples was ~0.02, the foamed core was ~0.08 and three-layer beams were ~0.067 in the range of vibration frequency up to 60 Hz.

Tests on bending are one of the effective ways to experimentally determine the elasticity and shear moduli. An important task in the implementation of composite materials in aerospace structures is the development of methods for determining the physical and mechanical characteristics of materials. The paper presents of tests for three-point bending of samples of metal-polymer composite material "GLAss-REinforced" Fibre Metal Laminate (GLARE) are presented. Examined samples, consisting of 17 layers, for which apparent interlayer strength of the results of tests on three-point bending was established by the method of "short beam". It was established that for the studied samples, interlayer shear mechanisms were realized at the ratio of dimensions of length to thickness of at least 10. Localization of fracture occurs in the area of the central layer, which corresponds to the requirements of standards for conducting tests of the method of short beams. Nonetheless, such GLARE tests are always accompanied by the occurrence of significant plastic deformations associated with the presence of aluminum layers in the structure of the material. With the elongation of samples of more than 10, a fracture mechanism is realized in them, during which delamination and loss of stability of the outer layers on the compressed side of the sample occur. When the elongation of samples of less than 4 four is implemented in samples takes place, the mechanism of destruction of indentation type with large nonlinear deformations. According to the test results, the dependence of the realised fracture mechanisms on the elongation of the samples is determined.

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