When it comes to the piezoelectric effect you can have a small quartz crystal and apply a force to it and get thousands of volts as a result. But if you took a quartz crystal and applied a thousand volts to it, would it just crack? For a quartz crystal to take a couple thousand volts charge (no current applied to the quartz just voltage) would it have to have a larger size to take the extra voltage. I'm thinking the higher the voltage applied to the crystal the more the molecules move.
dlgoff
Aug3-08, 10:04 AM
When you apply stress or deform certain crystals they produce an electrical potential across the crystals lattice. When you apply a potential across a crystals lattice, you get the reverse. The crystal will change it's shape.
Yes but can a quartz crystal withstand a large voltage in the couple thandsands of volts range. From what I was researching the crystal only moves around a nanometer when a voltage is applied. but does that movement increase to a larger amount when the voltage is increased? With a high enough voltage will the crystal break?
dlgoff
Aug3-08, 09:03 PM
I'm no expert on piezoelectric crystals but I beleive the change in length is a nonlinear funciton of voltage. I would also think high frequency pulses might create fractures.
fedaykin
Aug4-08, 01:12 AM
"I would also think high frequency pulses might create fractures."
I wonder if you could cause the crystal to crack (perhaps on an extremely small scale) through resonance in this manner.
zeitghost
Aug4-08, 03:27 AM
I suspect that if you applied kV to a quartz crystal it would fracture.
The manufacturers list maximum drive voltage in their specifications.
Watch crystals are particularly sensitive, being designed to work with very low power levels.