Acoustoelastic effect

Okay, so imagine you have a rubber band. You might have stretched a rubber band before, and noticed that it gets longer when you pull on it, right?

Now, let's think about sound waves. When sound travels through a material such as a metal pipe or an acoustic guitar string, it can cause the material to vibrate or shake a little bit.

The acoustoelastic effect is what happens when the vibrations or waves from the sound actually change the way the material behaves. It's sort of like when you stretch a rubber band and it gets longer, except in this case, the material being affected is something like a metal rod, instead of a rubber band.

This effect is very important in things like ultrasonic testing, which is a way to check for cracks or other defects inside materials like metal pipes or airplane parts. By using sound waves to make the material vibrate in a specific way, experts can tell if there are any problems inside the material that can't be seen with the naked eye.

So, in short, the acoustoelastic effect is what happens when sound waves change the way a material behaves, and it's really useful for testing materials to make sure they are safe and reliable.