Introduction. Carbon-carbon composite products feature high strength at temperatures up to 3000 C, resistance to aggressive environments, mechanical reliability and relatively low density. Up to now, there are no NDT established procedures for assessing the quality of composite products and their compliance with the technical requirements. Nowadays composites know-how can not guarantee the specified requirements. The paper provides the estimation of the composites ultrasonic testing equipment and procedure. Method. Subjected to studies were samples made a) in compliance with the required production technology, b) to ensure low mechanical properties, c) to ensure wrong frame geometry. An electronic module and transducers were developed so that a shadow method of sample examination in 3 orthogonal planes could be used. Subjected to studies were samples made a) in compliance with the required production technology, b) to ensure low mechanical properties, c) to ensure wrong frame geometry. An electronic module and transducers were developed so that a shadow method of sample examination in 3 orthogonal planes could be used. Results. The paper provides an analysis of relations between ultrasonic wave propagation velocity, signal amplitude, and the spectral maximum. It has been shown that a 200-500 kHz signal is appropriate to test all available samples, whereas a 400-500 kHz signal provides more information on the product and its defects. Defective samples shift the spectrum maximum to lower frequencies which can be used as the product rejection criterion. Possible directions in the further studies to improve the measurement accuracy have been emphasized. Conclusions. The findings show good opening for the carbon-carbon composites acoustic NDT.
nondestructive testing, rocket engineering, quality, structure, defects, material characteristics, composite, acoustic method, ultrasonic waves
1. Kren A.P., Protacenya T.A., Kutepov A.Yu. Mekhanicheskoe povedenie uglerod-ulerodnykh kompozitsionnykh materialov pri indentirovanii [Mechanics of CFRP under in-dentation]. 8-ya mezhdunarodnaya naychno-tekhnicheskaya konferentsiya “Priborostroenie-2015” [8th International Science and Technical Conference “Tools Engi-neering - 2015”]. V. 1, Minsk, BNTU, 2015, pp. 240-242 (in Russ.).
2. Fedorov A.V., Kren A.P. Pribor dinamicheskogo indentirovaniya dlya kontrolya mekhanicheskikh kharakteristik kompozitsionnykh materialov [Strength properties indentation testing device]. VI mezhdunarodnaya konferentsiya s elementami nauchnoy shkoly dlya molodezhi “Funktsionalnye nanomaterialy i vysoko-chistye veshchestva” [6th International Conference “Functional materials and high purity substancies], Moscow, IMET RAN, 2016, pp. 198-199 (in Russ.).
3. Shilova A.I., Lobanov D.S., Vildeman V.E. at al. Eksperimentalnoe issledovanie vliyaniya vysokotemperaturnoy obrabotki tkanogo napolnitelya na prochnostnye svoistva uglerodnykh kompozitov [Filler high temperature processing influence on CFRP strength]. Vestnik Permskogo natsonalnogo issledovatelskogo politekhnicheskogo universiteta [Perm National Research Technical University Proceedings]. 2014, no.4, pp. 221-239 (in Russ.).
4. Panin S.V., Burkov M.V., Byakov A.V. at al. Kombinirovannyy metod issledovaniya deformatsii i razrusheniya obraztsov iz uglerod-uglerodnogo kompozitsionnogo materiala po dannym akusticheskoy emissii, korrelyatsii tsifrovykh izobrazheniy i tenzometrii [CFRP samples distortion and fracture investigation using acoustic emission, digital image correlation and strain gagging]. [Sibirian Science proceedings, series “Engineering”], 2012, No4 (5), pp. 129-138 (in Russ.).
5. Medvedskiy A.L., Kornev Yu.V., Kurbatov A.S. Issledovanie fiziko-mechnicheskikh svoistv 4D uglerod-ulerodnogo kompozitsionnogo materiala na macro- i micro urovnyakh pri deystvii vysokikh temperatur [4D CFRP properties investigation under high temperature]. EJ “MAI Proceedings” 2010, issue 41, P.15. Available http://www.mai.ru/science/trudy/published.php?ID=23804 (in Russ.).
6. Sukhorukov V.V., Wainberg E.I., Kazhis R-Y.Yu at al. Introskopiya i avtomatizatsiya nerazrushayushchego kontrolya [Automation in NDT] Nerazrushayushchiy kontrol / Prakticheskoe posobie / pod ped. V/V/ Sukhorukova/ Kn. 5 [NDT. Practical Guide edited by prof. V.V. Sukhorukov Book 5]. Moscow. Vysshaya shkola, 1993, P.329 (in Russ.).
