Analysis and Processing of Acoustic Emission Signals Under Dynamic Loading of the Microstructure of Continuous Media

Abstract

The boundary problem of the propagation of acoustic emission signals at the conjugation of two continuous media is considered. A model of a two-layer continuous medium in the form of a chain of linear atoms connected by elastic bonds with a single-point developing defect is proposed. The force and displacement of the particles of the medium were chosen as the main variables. The solution of the boundary value problem in conjugate media using the Green's function and the Fourier transform is substantiated. It is shown that the energy spectrum of an acoustic emission is completely determined by the forc constants of materials and the forces initiating the appearance of acoustic emission signals. For a two-layer medium, a metal and a composite coating, significant differences were found in the nature of the acoustic emission signals arising in each material during bending. This feature makes it possible to separately identify and predict the state of each material in the associated environment. The presented solution of the equation of motion of a system of conjugated continuous media with the development of internal structural defects allows one to perform a spectral analysis of the differential operators of elastic energy and their expansion in terms of eigenvalues. Experimental verification of the proposed theoretical model of the energy spectrum of acoustic signals showed that the results of the study can be used to predict the degree of destruction of materials under loading.