RESEARCHES OF THE POSSIBILITY OF ASSESSING DAMAGE TO THREE-LAYER STRUCTURES BY IMPACT DAMAGE BY METHOD OF COMPUTED X-RAY TOMOGRAPHY

Abstract

This article describes the results of researches on the assessment of the applicability of the method of computer X-ray tomography for monitoring the internal structure of three-layer structures with carbon composite cladding and aluminum honeycomb, a general description of the method is given. It has been experimentally shown that the method of computed X-ray tomography allows one to evaluate the porosity of carbon composite plating, to identify stratifications resulting from impact. Comparative results of the non-destructive testing of a three-layer carbon composite sample made by autoclave molding from a unidirectional carbon tape and an adhesive epoxy matrix and aluminum honeycomb before and after impact are presented. It was revealed that for the upper lining of a carbon composite, the maximum number of macrodefects of the type stratification occurs directly in the impact zone and adjacent local areas, and leads to a change in the geometry of the skin and honeycomb aggregate, as well as a multiple increase in porosity in comparison with the results of the preimpact test. It should be noted that in the lower skin the porosity due to impact increases slightly, evenly distributed over the volume of the skin, which indicates the occurrence of cracking in the polymer matrix of the carbon composite.Thus, the method of computer x-ray tomography is an effective tool for controlling the damage of three-layer structures by impact.