Technical Consultant, Alcoa Technical Center, New Kensington, PA
Staff Technician, Alloy Technology Division, Alcoa Technical Center, Alcoa Center, PA
Pages: 10 Published: Jan 1995
Aluminum 1100 alloy fins in small heat exchangers are press fit onto copper tubing and require a protective coating to prevent excessive galvanic corrosion. This program was conducted to determine whether use of the ASTM Standard Practice for Cyclic Acidified Salt (Fog) Testing (G 85-A2), could effectively screen experimental, candidate coatings in a relatively short time. Two weeks of exposure, utilizing only unassembled panels, identified coatings that provided excellent protection. This compares very favorable with the existent quality control test that requires exposure of assembled units for 1000 hours (almost 6 weeks) exposure to the less corrosive, ASTM Standard Test Method of Salt Spray (Fog) Testing (B 117).
heat exchangers, aluminum fins, copper tubing, organic coatings, acidified salt (fog) testing, cyclic exposure
Paper ID: STP14042S