Processing characteristic and radiation resistance of various epoxy insulation materials for superconducting magnets

• We studied the processing properties of various epoxy matrices.
• We studied the radiation resistance of TGPAP-based and DGEBF-based composites.
• TGPAP-based systems are more suitable for VPI process than DGEBF-based systems.
• TGPAP systems present more radiation resistant than DGEBF systems.

Glass fiber reinforced epoxy-based composites were developed as insulating materials for fusion superconducting magnets. The processing properties of various epoxy matrices were investigated in terms of the isothermal viscosity at 45 °C. The interlaminar shear strength (ILSS) at 77 K and the thermal expansion coefficient (CTE) of the composites were assessed before and after gamma irradiation at ambient temperature up to 10 MGy. It is found that the TGPAP-based systems showed lower initial viscosities, longer working life and higher radiation resistance compared to the DGEBF-based systems with the same modifier. Furthermore, there was no significant effect of the irradiation dose on the CTE of the composites.