Word of the day: Flexoelectricity:

sonhouse

Fast and Curious

Science

27 Sep 16

sonhouse

Fast and Curious

slatington, pa, usa

Joined: 28 Dec 04
Moves: 53321

27 Sep 16

New for me anyway, semiconductors generating electricity when bent. Not Piezoelectricity where the electricity is generated by compression, Different effect:

http://phys.org/news/2016-09-semiconductors-electricity.html

apathist

looking for loot

western colorado

Joined: 05 Feb 11
Moves: 9664

28 Sep 16

1 edit

Apparently it is a piezoelectric effect modified by a strain gradient (wiki). I don't know what a strain gradient is.

sonhouse

Fast and Curious

slatington, pa, usa

Joined: 28 Dec 04
Moves: 53321

28 Sep 16

1 edit

Originally posted by apathist
Apparently it is a piezoelectric effect modified by a strain gradient (wiki). I don't know what a strain gradient is.

Gradient is just how the stress varies across a depth, so when bent, the inside curve may have more stress than the outside, which can be seen by laser interferometry.

Here are a bunch of images where you can see the distortions and stresses with this technique:

https://www.google.com/[WORD TOO LONG]

These devices can tell how well a telescope mirror is ground, and whether there is strain on the device.