Dielectric Properties of EPDM/SiC Composite under Huge Temperature Gradient

The high temperature superconductivity (HTS) equipment develop rapidly. Therefore, it’s increasingly more necessary to explore insulation materials of power leading, which can confront huge temperature differential and the electric field concentration. Nonlinear conductive composite has been proved to have the ability to improve the relief of steady and transient stresses simultaneously. However, dielectric property of the nonlinear composite is also a key factor in the insulation design of HTS power leading. In this work, we prepared the SiC/Ethylene propylene diene monomer (EPDM) composites with various filler contents of SiC (0, 3, 12 and 24 vol %), aiming to investigate the effects of SiC on the characteristics of EPDM composite. Morphologies and dielectric properties of the SiC/EPDM composite over a wide range of temperature and frequency were studied. Results indicate that when SiC is over the certain threshold there can form some pathways in the EPDM matrix, that means a latent impact of electrical field homogenization. Besides, EPDM/SiC composites have higher relative permittivity showing negative temperature dependence at lower frequency region. What’s more, the dielectric loss decreases in a wide range of frequency and temperature, meaning the potential of practical application of EPDM/SiC composites in the future. By using