calculating Natural Frequency 1

[doop4]

Hi guys,
Firstly, thanks to everyone for this wonderful forum. It's a great source of help.

To my question. I am trying to calculate the natural frequency of a piezo electric crytal I have. It's 10mm in diameter and 1 mm in thickness. Could someone please tell me which equation I'd have to use to calculate this? The material is PZT.

Thanks so much in advance

 

[doop4]

sorry forgot one more questionb . . .is the MECHANICAL RESONANCE FREQUENCY the same as a material's natural frequency?

 

[ajamnia]

to calculate the natural frequency properly, you need to specify your boundary conditions accurately. In other words, you need to specify, how your part is being held. I suggest you refer to "Mark's Standard Handbook for Mechanical Engineers" to find the right formula.

I just thought of another issue. Are you pre-stressing your crystal? This would impact your results as well

 

[GregLocock]

I disagree. The prestress in a disc of those proportions is not significant, for any reasonably stiff material (which crystals are).

doop, the answer to your second question is more or less no, since materials do not have a natural /frequency/. That is, geometry is (I think) always involved in calculating frequencies of mechanical systems.

Cheers

Greg Locock

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