Abstract
Products made of composite materials are widely used due to their strength and stiffness characteristics as well as corrosion resistance. However, in the course of operation, microdamages accumulate in composite materials, which, over time can lead to a loss of design performance. Various defects appear in the manufacture of composite materials. Since the destruction of composite materials is studied in less detail than metals, their use in products with increased requirements for reliability is associated with some degree of risk. To meet the high demands on reliability, it is necessary to apply modern methods of non-destructive testing, which allow identifying existing internal defects, localizing their position and determining linear geometric dimensions. Most of the traditionally used methods of non-destructive testing have certain disadvantages, which often make it impossible to obtain high-quality and most complete information about the defects. Composite materials are also becoming more widely used in electrical machines, which allows them to increase their specific characteristics. In electrical machines, the most loaded units are the shaft, the rotor banding, the stator teeth and bearing units. Therefore, the use of composite materials in these sites requires the creation of diagnostic systems to determine the residual resource and prevent accidents.
This paper presents methods for non-destructive testing of products made of composite materials. The main advantages and disadvantages of each method are given. The article also presents the developed method of eddy current testing for the carbon fiber rotor banding.
Keywords
Diagnostics, composite materials, non-destructive testing, eddy current method, electrical machines.
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