AFAIK, Same-o same-o -- they have exactly the same mechanical properties
for machining and welding. the T651 is T6 material that's been
mechanically stretched or stamped to straighten it.

Richard Hanley wrote:

I have a part to make that calls for 6061 T6. I have some 6061 T651.
Can anyone tell me the difference between them?
Thank You Richard

"Richard Hanley" wrote in message
...
I have a part to make that calls for 6061 T6. I have some 6061 T651.
Can anyone tell me the difference between them?
Thank You Richard

T6 is precipitation hardened; T651 is precipitation hardened and then
stretched or rolled. T651 has greater long-term stability, which makes it
more suitable for use in instruments and other applications that would
suffer from dimensional change over periods on the order of a year or so.

Machinability and other properties are considered to be the same for both,
or quite close.

This is from the ASM's _Metals Handbook_, 9th Edition.

--
Ed Huntress
(remove "3" from email address for email reply)

In article ,
says...
I have a part to make that calls for 6061 T6. I have some 6061 T651.
Can anyone tell me the difference between them?



Not enough to matter. Plain -T6 is more common in large sections.

http://www.engineersedge.com/aluminum_tempers.htm

Ned Simmons

Thank you to those who responded to this inquiry , you have been a great
help. Richard
Richard Hanley wrote:
I have a part to make that calls for 6061 T6. I have some 6061 T651.
Can anyone tell me the difference between them?
Thank You Richard