We had a diving job a few months back in Florida. We normally have our 50 cf aluminum bailout cylinders refilled every job, usually at a local shop where the job is. They had just had their 5 year hydro test, and the shop in Memphis that did it also stripped the flaky paint off the outside and spray bombed them. No big deal either way. But the FL dive shop said most places won't refill a repainted tank. I asked him why, and he said a couple shops had had tanks explode while being refilled. Something about someone had a buddy in a body shop repaint their tank and when they baked the paint job, it changed the tank somehow causing it to explode when it was filled.

I called BS, but I decided not to argue with the guy. I think he might have confused painting with powdercoating. I seem to remember the temperature for baking finished paint job on a car was only like 120°. Heck it gets hotter than that in the car in the summer and I've left bottles in that temp before. But the baking was years ago when emamels and lacquers were in widespread use and the urethanes were just coming out. Do the modern paints even need this step?

Dont NEED it but most collision shops bake because you can paint and assemble more cars quicker than letting them air cure. Temp is around 140 F

I'm calling BS on the notion that a tank that has been heated is subject to explosion!
Not only have my SCUBA tanks been pretty hot.... BUT.... I've worn aluminum SCBA (fire department) tanks in temps of several hundred degrees!!!