03-29-2017, 09:32 AM
Copper is annealed by quenching or air cooling. When annealing copper by water quenching, it remains somewhat softer and is more malleable. This is better when using it for gaskets, as it more easily forms to take the shape of and seal the adjoining surfaces when compressed. Copper is also annealed by air cooling, but I think it gains back some of its hardness that way and makes it slightly less favorable to form as a result. I'm sure someone can correct me or elaborate more in detail.