Aluminum 7049

Principal Design Features

7049 is basically a forging alloy. It is heat treatable with very good resistance to stress corrosion cracking.

Applications

Primary applications for this alloy involve structural forgings, such as used in the aircraft or missile industries.

Machinability

The machinability of 7049 is good in the heat treated state. As with most of the aluminum alloys the use of oil lubricants is recommended during machining.

Forming

This alloy is NOT intended to be cold formed. Forming is done by hot forging or hot forming.

Welding

Welding of 7049 alloy should be avoided. It may be possible to do tungsten inert gas welding, but best to consider this as an alloy that is not normally welded.

Heat Treatment

Solution heat treatment is done at 875 F for adequate time to allow thorough heating, followed by a water quench. The alloy may be aged after the solution heat treatment – see “Aging”.

Forging

Forging is done in a relatively narrow temperature range of 820 F down to 720 F.

Hot Working

Hot working would be accomplished in the same temperature range as for forging, that is 820 F to 720 F.

Cold Working

Cold working of this alloy should NOT be done.

Annealing

Not applicable to this alloy as it is not cold worked.

Aging

Aging, or precipitation hardening, is done in a 2 step heat treatment. First allow 48 hours at room temperature, followed by 24 hours at 250 F and air cool. Second step is 14 hours aging at 320 F and for 14 hours followed by air cooling.