Analysis of peculiarities of polymer matrix microstructure in PCMs formed under the influence of electrophysical effects

Abstract

The microstructure of monolayer samples formed by 3D printing from composite prepregs reinforced with continuous carbon fiber, followed by treatment in a cured state by exposure to ultrasonic vibrations and a microwave electromagnetic field, has been studied. It has been shown that high-power ultrasonic exposure causes macro-changes, which are characterized by a decrease in the number and transverse dimensions of delaminations (cracks) from 0.05–0.1 mm to 0.01–0.02 mm and a decrease in the height of microrelief elements by almost an order of magnitude. Changes caused by exposure to a microwave electromagnetic field are more apparent when examining the end surface with an increase from ×1000 to ×10000. The control samples revealed fibers consolidated by binder in combination with unfilled gaps in a ratio of about 50:50, with individual globular fragments of frozen binder on their surface. The samples after microwave exposure revealed the presence of large areas without defects, completely uniformly filled with binder, fibers from all sides are in contact with the binder, in which there are voids no larger than 5 × 1.5μm in size. Greater orderliness of the structure of monolayers is most typical for samples with two-stage processing, including preliminary ultrasonic and subsequent.