Experimental Evaluation of the Corrosive Potential of Flux Residue Cleaning Agents.

The results obtained from this study were used to assess the potential corrosion problems associated with using an aqueous MSI-7000 flux remover for electronic and mechanical equipment repairs. This candidate cleaner is being considered as a replacement for the solvent chloroflurocarbon and chlorinated hydrocarbon cleaners that are currently being used at the Aerospace Guidance and Metrology Center AGMC which is located in Newark, Ohio. Technical specialists at AGMCMAEL and Battelle were responsible for developing a test plan which would quantify the level of corrosion occurring on specimens that were configured to simulate all materialcoating combinations found at AGMC. Testing included the exposure of numerous coated test specimens to a warm, humid environment. Post-test microscopic and metallographic examinations then were performed to determine the level of subcoating corrosion damage on specimens containing fluxcleaner residues. A comparison between the damage noted on control nonfluxed specimens, and specimens that were fluxed and cleaned with both an aqueous and a solvent cleaner were made. The results of these examinations confirmed that the candidate water-based cleaner did not promote any more corrosion on the surfaces of the tested specimens than did the conventional solvent cleaners. In most instances, the extent of damage occurring beneath the various coatings applied to several substrates bare and plated which simulated both circuit board and casing materials was considered minimal. Neither cleaner promoted appreciable amounts of corrosion after four weeks of exposure to the test environment.