AlCoat - Strong, Tight, and Ultrathin Corrosion Protective Coatings

Purpose and goal

Develop an ultra-thin coating that protects aluminum heat exchangers against corrosion in seawater as a complement to titanium heat exchangers and to implement the coating process for aluminum plate heat exchangers.

Expected results and effects

The coating created an acceptable corrosion protection for heat exchangers in aluminum but with a coating thickness that became 4 times as thick, which meant that the heat transfer was reduced and more plates were required to cope with the thermal duty.

Planned approach and implementation

Aluminum heat exchanger plates were pressed and given a primer coating and then a top coating. Complete heat exchangers with coated aluminum plates were tested in a seawater laboratory and passed a 12-month test at 70C.