AUTOMATION OF THE PROCESS OF DIAGNOSING SUBSURFACE STRATIFICATIONS ON COMPOSITE STRUCTURES OF AIRCRAFT

Authors: Davydov I.A., Kondryakova М.А.
IRSTI 73.37.41

Abstract. The article prepared by the author is a study aimed at automating the diagnosis of subsurface stratifications on composite structures of aircraft that are formed during post-impact damage. This article presents the results of the tests – the blow was inflicted on “witness samples”, that is, from a composite material that is used in the designs of civil aircraft. The blow was applied with tips of various shapes and diameters, allowing to simulate the operational defects of aircraft as much as possible. The impact was carried out in the range from 5 J to 80 J, impacts below this limit do not lead to delamination of the composite material, impacts above the specified limit lead to cracks on the surface of the composite material and significantly change the shape of the structure, which is beyond the scope of this study. Using regression analysis based on the test results, the ratios of geometric variables of defects and shock effects were obtained, which allows modeling the width, depth and shape of the defect from the impact energy and vice versa. Based on the data obtained, the author has developed software in the Java programming language, which calculates subsurface stratification in post-impact damage based on geometric data of a defect on the surface of a composite material. Automation of the post-impact damage diagnostics process significantly reduces the likelihood of a subsurface defect on a composite material being missed by the engineering and technical staff of an aviation enterprise, and also automatically issues recommendations on the replacement or repair of an aircraft composite structure. The relevance of the study of composite materials is of particular importance in connection with the development of a completely new domestic liner MS21-310, in which the wing is made of multilayer carbon fiber. The developed software based on the test results will have an impact for the successful provision of after-sales operation of the aircraft and maintenance of airworthiness.

Key words: composite materials, aviation, defect, operation of aviation equipment, maintenance.