Kevin, Devcon makes a variety of metal (aluminum, steel and titanium) reinforced puttys as well as ceramic mixes. I've used these in a variety of repairs on refinery vessels with great success. They aren't cheap, Plastic Titanium is $100 a pint as I recall, but if you do proper surface preparation the stuff is will not fail. As with all epoxy work, surface preparation is the key.

Rick Girard