What temp can alloys be heated to without affecting mech props?

[luket]

Does anyone have guidelines for acceptable temperatures that a given alloy can be raised to and then cooled again to room temp without affecting its mechanical properties? I have a shrink fit bushing (C63000 nickle alum bronze) in a housing (AL 7050-T7451). I am curious how hot I can heat the assembly to aid in removing the bushing, but not damage the materials. I have looked at the annealing temps for the 7050. If I stay below those temps, will the material remain unchanged? I have even less info on the C63000. Any guidelines or info sources you could point me to would be appreciated.

Luke

 

You shall heat the 7050 aluminum alloy in a temperature below the artificial aging heat treatment temperature (in this case the second step aging temperature) so, 140ºC during the necessary time is recommended. By the way, at this temperature the C63000 bronze will be not affected too.

Good luck

 

[bilge]

Have you considered cooling the assembly down, e.g. in liquid nitrogen or in dry-ice and alcohol, to see if the parts could be loosened?

 

[WKTaylor]

also...

If the bushing [or a solid bolt] is in high interference [or is otherwise "stuck" in-place] AND it is NOT destined to be salvaged, then consider step-drilling/reaming thru the center, until the interference load disappears... then pop the bushing out. NOTE: use plenty of coolant to minimize heat-build-up! Regards, Wil Taylor