Heat Treating 6061-T6

[Creigbm]

I have a question on heat treating 6061 from T4 to T6. I have the information on what temperature to bake the metal to. After 8 hrs, do you simply open the door and allow it to air cool or leave the oven door closed to get a more gradual cooling process? Thanks.

 

[unclesyd]

Take it out of the oven.

What is the type 6061 Al product your are dealing with, extrusion, rolled, etc ?

 

[Creigbm]

Thanks unclesyd,

We are using about 1/2" plate. Here is some more info on what I am trying to accomplish. I have had some T4 sheet metal rolled and riveted together. The base ring holding the assembly together is 6061-T6. I am trying to determine if baking the T6 at 350 degrees for 8 hrs will significantly degrade the strength of this T6 base ring (I need to bring the T4 sheet metal to T6...the reason for using T4 is because it is easier to work with). I found smoe info in Mil Handbook 5, but I would rather test this out for myself. So to make a long story short, I have some T6 dogbone shaped test pieces make that we are going to bake and test the tensile strength.

 

[unclesyd]

Be careful with your heat treatment of the plate, normally you hold 6061 plate for a longer period of time for precipitation treatment to T6, 18 hrs @ 320°F.

If the physical values are off try a longer time at temperature.