Microelectrode Test Configurations for Measurement of Galvanic Current Under Saline Drops in Simulated Atmospheric Conditions

This work investigates galvanic corrosion of UNS A97075 (AA7075-T6) coupled with a stainless steel UNS S13800 (CRES 13-8) in a simulated atmospheric environment under electrolyte droplets. Three different electrochemical test configurations were compared to understand galvanic corrosion in droplet electrolytes. Micro-pipets were utilized to electrochemically examine alloys and determine galvanic corrosion current from droplet polarization scans. Additionally a novel galvanic corrosion cell with two distinct droplet half cells joined by a micro-pipet salt bridge was constructed to observed galvanic atmospheric corrosion rates in dynamic environmental conditions. The last configuration examined a galvanic couple in contact with a single drop and exhibited corrosion behavior distinct from the latter design to due to reaction product interactions.