Low-temperature thermal conductivity of polyimide irradiated with Ni ions
نویسندگان
چکیده
The planned International Facility for Antiproton and Ion Research (FAIR) will consist of a superconducting double-ring synchrotron offering ion beams of intensity increased by a factor of 100-1000 compared to the existing GSI accelerators. Materials close to the beam tube will be exposed to secondary radiation of neutrons, protons, and heavier particles, possibly limiting reliable function and lifetime of device components. The present study investigates the radiation hardness of insulating components with focus on polyimide used as electrical insulation of the quench heaters of superconducting magnets. In this special application, polyimide has to provide (i) electrical insulation of the heater as well as (ii) heat transmission to the magnet to guarantee thermal exchange to the superconducting coils. In case radiation-induced degradation decreases the thermal conductivity, higher heating powers for a given temperature step would be required. We thus performed measurement of low temperature thermal conductivity of ion-irradiated polyimide.
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