where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -
812 views
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


 
 Reply 
 
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 ------------




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


 
 Reply 
 

Product Spotlight

Immersion systems

ScanMaster ultrasonic immersion systems are designed for high throughput, multi shift operation in a
...
n industrial or lab environment. These fully integrated systems provide various scanning configurations and incorporate conventional and phased arrays technologies to support diverse applications, such as inspection of disks, bars, shafts, billets and plates. All of ScanMaster immersion systems are built from high accuracy scanning frames allowing for scanning of complex parts and include a multi-channel ultrasonic instrument with exceptional performance. The systems are approved by all major manufacturers for C-scan inspection of jet engine forged discs. Together with a comprehensive set of software modules these flexible series of systems provide the customer with the best price performance solutions.
>

Wireless TOFD scanner

Quick, accurate and highly reproducible welds testing. The System operates wirelessly and is compat
...
ible with any type of Windows based Laptop, Desktop or Tablet.
>

Echomac® Small

Available with up to eight channels of electronics to detect and evaluate thickness, flaws and eccen
...
tricity, this UT tester is housed in a convenient, smaller cabinet. This instrument can be used in conjunction with bubbler or immersion tank systems, or with a test bench or in laboratory applications. The Echomac® Small is available in the FD4, FD6 or FD6A versions.
>

On-Demand Webinar: Advanced Ultrasonic Techniques for HTHA Detection & Assessment

In the Oil and Gas industry, High Temperature Hydrogen Attack (HTHA) can occur in steels operating a
...
t high temperature, usually above 205°C (400°F). Early stages of HTHA are very difficult to detect. Join us for a webinar presented by Guy Maes, Zetec Sales Engineer Director. The webinar will demonstrate how advanced ultrasonic techniques are deployed for efficient and reliable HTHA inspections.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window