A method for measuring the corrosion rate of materials in spallation neutron source target/blanket cooling loops

This paper summarizes the ongoing evaluation of the susceptibility of mater ials in accelerator target/blanket cooling loops to corrosion. To simulate the exposure environment in a target/blanket cooling loop, samples were irr adiated by an 800MeV proton beam at the A6 Target Station of the Los Alamos Neutron Science Center (LANSCE). To accomplish this, a cooling water loop capable of exposing corrosion samples to an 800MeV proton beam at currents upwards of 1 mA was constructed. This loop allowed control and evaluation h ydrogen water chemistry, water conductivity, and solution pH. Specially des igned ceramic sealed samples were used to measure the real-time corrosion r ates of materials placed directly in the proton beam using electrochemical impedance spectroscopy (EIS). EIS was also used to measure real-time corros ion rates of samples that were out of the proton beam and "downstream" from the in-beam samples. These out-of-beam probes primarily examined the effec ts of long lived water radiolysis products from proton irradiation on corro sion rates. An overview of the LANSCE corrosion loop, the corrosion probes, and data from an in-beam alloy 718 probe are presented. Published by Elsev ier Science Inc.