FrontEngineDragsters.Org Forum

Technical => Roo Man's Room => Topic started by: George on August 06, 2014, 11:09:41 AM

Title: 6061-T651
Post by: George on August 06, 2014, 11:09:41 AM
I ordered a piece of aluminum 6061-T6 for a new mid plate and it is 6061-T651. I have looked online and don't think there is a problem but it's something I haven't seen before. Any problems associated with this material?

Thank You. George
Title: Re: 6061-T651
Post by: dreracecar on August 06, 2014, 12:04:17 PM
To get to the -T6 temper, the 6061 is heated to about 990F, then quenched in water, then aged at about 350F for around 8 hours. That changes the typical yield strength from 8 ksi to about 40 ksi- fairly substantial.

But that quenching in water puts residual stresses in the aluminum, since there is a surface-to-center cooling gradient. The -T651 designation means the mill took that extrusion and gave it a 1% to 3% stretching, or permanent set, to get rid of some of those residual stresses.
Title: Re: 6061-T651
Post by: George on August 06, 2014, 05:33:09 PM
To get to the -T6 temper, the 6061 is heated to about 990F, then quenched in water, then aged at about 350F for around 8 hours. That changes the typical yield strength from 8 ksi to about 40 ksi- fairly substantial.

But that quenching in water puts residual stresses in the aluminum, since there is a surface-to-center cooling gradient. The -T651 designation means the mill took that extrusion and gave it a 1% to 3% stretching, or permanent set, to get rid of some of those residual stresses.

Thanks Bruce. It all sounds good to me.
Title: Re: 6061-T651
Post by: Nightmare AA/FA on August 06, 2014, 07:11:25 PM
To get to the -T6 temper, the 6061 is heated to about 990F, then quenched in water, then aged at about 350F for around 8 hours. That changes the typical yield strength from 8 ksi to about 40 ksi- fairly substantial.

But that quenching in water puts residual stresses in the aluminum, since there is a surface-to-center cooling gradient. The -T651 designation means the mill took that extrusion and gave it a 1% to 3% stretching, or permanent set, to get rid of some of those residual stresses.

Now there's a guy who knows his metal.
Title: Re: 6061-T651
Post by: dreracecar on August 06, 2014, 09:24:06 PM
Also how to copy and paste