Properties of an Epoxy Composite Material Filled with Modified Minerals

Dispersed fillers (basalt, chromite) are modified in an induction installation at a power of 2 kW and a processing time of 60 s, which ensures a short-term high-temperature effect of high-frequency (HF) currents on the fillers and, as a result, improves the characteristics of the filled epoxy compounds based on them. The chemical composition of the fillers is found to change, which is associated with the removal of unbound moisture, an oxide film, and the oxides of the substances the decomposition temperature is lower than the modification temperature from the surface of basalt and chromite particles. Electron microscopy data demonstrate that basalt particles acquire a needle-like shape after exposure to HF currents, which positively affects the physicomechanical characteristics, since such a filler exerts a micro-reinforcement effect. Chromite particles weakly change their structure after HF current treatment. The study of the dielectric characteristics of the mineral fillers before and after HF current treatment shows that the dielectric constant increases significantly for basalt and chromite, indicating a change in their structure; this increases the strength characteristics from 7 to 17%.