I have some machined aluminum pieces to bend for a customer. I would prefer not to anneal them as the not bent parts should be as stiff as possible. They are only 1/4" thick and I was going to go with a 5/16 inside radius 45 degree bend. Does anyone know if this is likely to crack or can I go ahead and bend it withot annealing.

It should work. Is there any way you can try a sample first? With that size radius and only bending to a 45 you will probably get away with it.

The customer dropped of another piece of material this morning and I bent it 90 degrees and then straightened it back out. No cracking so I am going to bend them cold on the flypress.

I'm sure you're talking 6061 T6 (most common) but there ARE other alloys that are not as forgiving as 6061 (like 7075). Glad it worked out for ya.

might get lucky bending cold against the grain... even in line with the grain might be ok but you risk hairline cracking...annealing the bend area only isnt much trouble

shouldn't have any troubles only doing a 45 especially with that large of radius. I agree, test piece it first. And, if you are that worried about it, then use a dye penetrant and inspect the inside and outside radii for cracking.

 

-Hillbilly