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- since 1996 -
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Technical Discussions
Phil Harper
Director, Tribosonics
Tribosonics Ltd, United Kingdom, Joined Feb 2004, 10

Phil Harper

Director, Tribosonics
Tribosonics Ltd,
United Kingdom,
Joined Feb 2004
10
03:16 Feb-17-2004
Piezo crystal centre frequency

Hi,
A rather basic question i fear, but i don't have an answer at the moment.
I have got a piezo-ceramic crystal that is 1mm thick and 16mm diameter. I simply want to work out what the centre frequency of it is?

Any ideas?

Thanks

Paul A. Meyer
R & D,
GE Inspection Technologies, USA, Joined Nov 1998, 47

Paul A. Meyer

R & D,
GE Inspection Technologies,
USA,
Joined Nov 1998
47
05:47 Feb-17-2004
Re: Piezo crystal centre frequency
Hi Phil,
The product of the thickness and the resonant frequency is usually a constant, in this case it is called the thickness frequency constant. PZTs usually have a value around 2000 Hz-m. Dividing this value by the thickness (.001 m) yields the resonant frequency ~ 2 MHz. In you situation, you should identify the material, then obtain the frequency constant from the manufacturer, then perform the above calculation. Because the material can resonate in other directions (other modes), ensure that you ask the manufacturer for the "thickness frequency constant".
Alternatively, you can measure the actual resonance of the piece by plotting its impedance spectrum or inspecting it with an ultrasound instrument, but the calculation is easier.
I hope this helps.
Paul

----------- Start Original Message -----------
: Hi,
: A rather basic question i fear, but i don't have an answer at the moment.
: I have got a piezo-ceramic crystal that is 1mm thick and 16mm diameter. I simply wantto work out what the centre frequency of it is?
: Any ideas?
: Thanks
------------ End Original Message ------------

shan
shan
02:03 Jun-20-2005
Fr Vs G
what happens if the value of G (mS) is very low in a transducer?

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