N.N. Beklemishev - Dr. Sc. (Phys.-Math.), Professor, Head of Department of Physics, Russian State Technological University. E-mail: nnbeklem@mati.ru S.A. Kuznetsov - Post-graduate Student, Russian State Technological University. E-mail: kuznetsov_s_a@mail.ru A.P. Zaharov - Post-graduate Student, Kazan Research Center of RAS. E-mail: alex.zakharov88@mail.ru N.V. Kalenova - Ph. D. (Phys.-Math.), Deputy Head of Department of Physics, Russian State Technological University. E-mail: perepljuika@bk.ru

Fatigue failure of structural materials plays an important role in the evaluation of durability, particularly in the end of the calculated resource. Investigation of the features of macro and micro dynamics of fatigue fracture requires a comprehensive process analysis at different scale levels. We propose a method of experimental study of fatigue fracture of materials under biaxial loading, based on the combined analysis of data from the microscope, which is measured by the dynamics of crack growth at the macro level, fractographic analysis of the crack surface, allows to evaluatemicrodynamics destruction, and acoustic emission data. Acoustic emission allows us to analyze the dynamics of fracture at low levels of scale and highlight the prevailing mechanisms of destruction. The complex analysis of the dynamics of fatigue failure D16T under biaxial loading using the methods of acoustic emission analysis and fractographic fracture surface. A comparison of different methods possible to identify correlations between the predominant failure mechanisms and parameters of acoustic emission. The results can be used to introduce the criterion of destruction, taking into account the kind of stress-strain state. Experimentally determined that dynamics of constant fatigue failure of the material can match a different set of parameters of acoustic emission signals. It is shown that this phenomenon can be explained by the dependence of the parameters of the sound generated by the state of the environment in the area of destruction. Spotted change the character of acoustic emission signals when changing the dynamics of destruction. Maximum intensity of the signals for all of the samples was achieved during the predominance of local plastic deformation. Further intensive destruction match less intense signals that can be explained by a change in the mechanism of formation of a wave of sound to the accumulation of damage in the area of destruction. An analysis of the experimental data obtained qualitative agreement parameters of acoustic emission signals and the mechanism of fatigue failure of cross-sample D16T.

 

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