ИССЛЕДОВАНИЕ ВЛИЯНИЯ СХЕМЫ ВОЗДЕЙСТВИЯ СВЧ ЭЛЕКТРОМАГНИТНОГО ПОЛЯ НА ТВЕРДОСТЬ ОТВЕРЖДЕННОГО УГЛЕПЛАСТИКА С НАНЕСЕННОЙ НА ПОВЕРХНОСТЬ МОЛНИЕЗАЩИТНОЙ СЕТКОЙ

Abstract

Currently, the use of fiber-reinforced polymer composite materials (PCM), in particular, carbon plastic and fiberglass, is much promising in manufacturing structural elements of aircrafts and wind turbines. In order to increase the resistance of these materials to static electricity and lightning strikes when passing storm fronts, the structure of the PCM includes various lightning protection coatings (LPC). The most common LPC are in the form of copper grids. The fin assembly and planes of aircrafts and also large-sized blades of wind turbines are exposed to cyclic high-amplitude and low-frequency bending loads as well as vibrations. Collisions with solid objects are quite possible. Thus, hardness is one of the key characteristics of PCM that determines their performance properties. Strength and endurance of PCM components can be increased by short-term exposure to a microwave electromagnetic field. The presence of a built-in metallic structure brings additional uncertainty in the tolerance to operating loads by anisotropic PCM, as well as in the process of their interaction with an ultrahigh frequency electromagnetic field. Research was performed on the hardness of carbon fiber-reinforced plastics with built-in LPC using various exposure schemes to a microwave electromagnetic field: from the side of the LPC, from the side opposite to the LPC and sequential processing from both sides. It was found that short-term processing in a microwave electromagnetic field with energy flux density of (17-18)×104mW/cm2 did not lead to any change in the initial hardness of the surface of the samples. However, the uniformity of hardness distribution on the surface of the samples in- creased by 35.8-70%, thus ensuring a more adequate tolerance to loads of different nature. The obtained results can be used in the development of finishing technologies to post-process PCM components and improve the latter’s stability to dynamic loading.