Reducing Defectiveness of the Interphase Layer in Polymer Composite Materials after Exposure to a Microwave Electromagnetic Field

The microstructure in the area of the interfacial layer (IFL) of structural carbon and glass-reinforced plastics after exposure to a microwave electromagnetic field in the cured state has been studied. It was found that the IFL of control and experimental samples is characterized by the presence of structural formations of complex shape with granular morphology, the element sizes of which are 10-20 nm. The IFL of control samples is characterized by increased defectiveness, expressed in numerous microcracks of 100-500 nm in size and more, and matrix delaminations from the fiber up to several hundred nanometers in size. In experimental samples, such defects are practically not detected. In the modes of microwave exposure, corresponding to the temperature of the temporary restoration of the plasticity of the matrix, the formation of waviness is noted. The research results allow us to conclude that one of the reasons for the increase in the physical and mechanical properties of cured polymer composite materials as a result of microwave exposure is a significant reduction in defectiveness in the IFL.