On Fri, 28 Nov 2008 22:04:59 -0500, GeoLane at PTD dot NET wrote:

On Fri, 28 Nov 2008 22:43:02 +0000 (UTC), David Lesher
wrote:

I'm envisioning a gadget I can see a use for....

It would be made from spring steel, say coat-hanger diameter, in s
specific shape. Key to its use would be it could be bent in one way to
deploy it, but it would revert to its original shape.

What controls how much it can be bent without altering the final shape?

Umm. The modulus of elasticity????? Is this multiple choice?

RWL

As Ed mentioned the modulus of elasticity is pretty much the same for all
steels. What makes a difference to how far you can bend something before
it yields is the ratio of the modulus of elasticity and the yield
strength of the material.

Heat treatment and high carbons increase the yield strength, until
eventually the material snaps instead of permanently bending. But they
don't significantly change the modulus of elasticity.

--
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com

Need to learn how to apply control theory in your embedded system?
"Applied Control Theory for Embedded Systems" by Tim Wescott
Elsevier/Newnes, http://www.wescottdesign.com/actfes/actfes.html