The paper describes an experimental study involving investigation of corrosion possibilities in cooling circuit of an in-house developed 10 MeV, 6 kW S-band industrial electron linear accelerator, comprising of vacuum brazed multiple OFE copper cavities. The study was performed on vacuum brazed OFE copper specimens in process water used in the cooling circuit of the accelerator structure. The results of the study has demonstrated that surface of the brazed OFE copper specimens, exposed to stagnant process water, develops passive oxide layer in the initial period of specimen's exposure. This oxide layer protects underlying substrate from further corrosion. In contrast, specimens exposed to flowing process water displays relatively higher rate of corrosion. On the basis of short term immersion tests (for 45 days) in flowing conditions the estimated rate of general corrosion was found to be about 0.18 mils/year (equivalent to 4.5 µm/year) which is quite low. However, a long term corrosion study in simulated process loop would provide more useful information regarding corrosion behaviour of the brazed joints of the accelerating structure.

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