Karl Townsend wrote in
rec.crafts.metalworking on Thu, 10 Feb 2011 18:01:49 -0600:

I'm preparing to machine several AL 7075 T6 forgings...

"The Kid" (my son) tells me I should anneal before machining because
there will be hard brittle spots. Easy enough to do at the anneal temp
of 775 (not sure how long). But, then I haven't got T6 grade 7075 AL
anymore. How would I get it back to T6 grade?

Or, am I better off with plan "A"? Don't anneal.

My vote is don't anneal. Hard spots in 7075 aren't like hard spots in
steels.

--

Dan H.
northshore MA.