Brazing

c'mon chris, you should know better than making broad brush statements like this. Heating can do two things dependent on what follows: if you cool the metal fast it goes harder but more brittle, cool it slowly - in warm air, say - and you can make it softer and less brittle. Fast heating or cooling make the metal structure less predictable if I remember correctly.

I doubt the OP was would have been flash cooling the frame, I was speaking to circumstance. But yes you are right and i should have pointed this out