PSI - Issue 41

M.Sh. Nikhamkin et al. / Procedia Structural Integrity 41 (2022) 759–765 Author name / Structural Integrity Procedia 00 (2019) 000–000

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c Fig. 6. Results of registration of the main test parameters: (a) – changes in the resonant frequency of the tests; (b) – change in the total number of acoustic emission events; (c) – change in the number of acoustic emission events per unit time.

4. Conclusion This article discusses several methods for assessing the degree of damage to a sample during fatigue testing by recording its various parameters - the resonant frequency of the sample, changes in temperature and deformation fields on the surface, as well as acoustic emission signals generated by it during destruction. The obtained experimental data indicate that all the considered research methods can be used to obtain information about the various stages of sample destruction. For example, deformation fields can be used to determine the areas of delamination in a sample, temperature fields can be used to identify local areas of increased self-heating of samples, the resonant frequency of vibrations and analysis of acoustic emission characteristics can be used to indirectly determine significant damage in a sample. The joint registration of these parameters makes it possible to carry out in a complex the identification of the facts and moments of the appearance of fatigue damage in samples of composite materials. In addition, the experimental data obtained in this way can be used to verify and identify mathematical models.