The changes of mechanical properties of epoxy/mica insulation materials in aging process

The dynamic mechanical properties of epoxy/mica glass-fiber reinforced composites were studied at different aging stages under electrical-thermal stresses and thermal-mechanical stresses. A new method was proposed to calculate the apparent activation energy of glass transition (AAEGT) of epoxy/mica based on dynamic mechanical analysis (DMA) curves. It is suggested that dynamic mechanical parameters can be used to describe the aging characteristics of epoxy/mica.