I'm having a rather odd problem I've never run into before. I got a bunch of scrap titanium plate (0.135") from a scrap yard a while ago and finally got around to playing with it. I've forged some bracelets out of it and after acid etching and heat anodizing they come out looking pretty neat. Now here's the problem: they don't stay bracelet shaped. Even though I got them to a nice yellow heat at points while shaping them they very very slowly open up, trying to flatten out again. I've had to put mine in a vice twice now and close it up (in about 5 weeks). I did some looking online and apparently ti plate has "memory" to its original form. Has anybody else had this problem forging ti ? And has anyone come up with a solution for it ? I would have thought that the high heat would kind of set its form again, but I guess not.

Thanks for the help.

Cheers,

Drq

Alpha alloys are not heat treatable. Beta alloys are heat treatable and retain their structure when quenched. Maybe you have the latter this time...

Are you sure it's ti? There are memory metals out there.

I've done a lot of ti forging and never ran into that problem.

I haven't run into that problem either but I try to stick with the CP 1 & 2 grades.

Learn something new every day. I looked up "metal memory" and found this: The three main types of shape-memory alloys are the copper-zinc-aluminium-nickel, copper-aluminium-nickel, and nickel-titanium (NiTi). So maybe you got a piece of Nitinol?

Here's a video you may like in regards to that: http://www.youtube.com/watch?v=fLGaF6cWl04
I remember the government agency I worked for back in the 70's had a scroll of Nitinol in a glass box and just by changing the temperature it would straighten out and then go back to the scroll shape. They had a scroll drawn on the one wall so you could see that it went exactly back to shape each time. This happened every 5 minutes for years!

So instead of being frustrated with it, see what else you can make with it using this feature! Wish I had some of it!

I'm pretty sure its Ti, I'm basing that off the facts that it sparks white, is non magnetic and oxidizes pretty colours. When you start getting into these super alloys I'm way over my head. Also for the application it was used in I don't think it would be anything reallllly expensive. There was about 60 sq ft of it lining a pipe that came out of a osb mill in town. I wish it happened that fast. Its more moving and 1/8th of an inch over weeks as opposed to seconds.