# Effect of Radiation up to 30 MGy on Mechanical and Dielectric Properties of Polymers for Superconducting and Resistive Magnets

## TL;DR

This study examines how radiation up to 30 MGy affects the mechanical and electrical properties of various polymers used in particle accelerators and detectors.

## Contribution

The study introduces a comparative analysis of radiation effects on multiple high-performance polymers and composites relevant to accelerator applications.

## Key findings

- Radiation degradation of breakdown voltage occurs after mechanical property degradation.
- Mechanical strength thresholds were used to assess radiation hardness across materials.
- Gamma irradiation effects were evaluated using bending tests, hardness measurements, and breakdown voltage tests.

## Abstract

The effect of ionising irradiation up to 30 MGy on the mechanical and dielectric properties of different polymers for potential use in particle accelerators and detectors was compared in this study. The materials studied include the high-performance polymers PEEK, PPS and PEI; pure anhydride- and amine-based epoxy resin systems for coil impregnation and adhesive bonding; glass fibre epoxy composites; and FDM, SLA and SLS 3D-printed materials and polyurethanes. Gamma irradiation was applied in ambient air at an approximate dose rate of 2 kGy/h. Dose-dependent radiation damage was monitored by three-point bending tests, Shore A hardness, tensile stress–strain measurements and breakdown voltage tests in liquid nitrogen. Radiation hardness was rated according to two criteria: the dose at which the initial mechanical strength is halved and the dose at which the mechanical strength is reduced below a certain threshold value. The degradation of the breakdown voltage was preceded by the degradation of mechanical properties.