Yes, I worked at IMR. I had an internship there for the summer of 2008. I did do some work on Al, but mostly steel and Nickel superalloys. The corrosion work I did was all steel and copper, though. I'm not sure what solution one would use for an Al radiator. Al is different from steel and copper in that pure aluminum is very susceptible to oxidization- what prevents it from flaking away like steel does when it rusts is that the density of aluminum oxide is not very dissimilar from Aluminum, so it doesn't heave up and flake off like iron oxide does. So the aluminum oxide forms a protective barrier.(For more reading, google Pilling-Bedsworth ratio) Some things will penetrate this aluminum oxide barrier, though- mercury and gallium, both of which are severely restricted for air transportation. If they came into contact with the aluminum airframe, severe damage could result as the aluminum oxidized away with no protective layer.