I don't suppose anyone here has any experience?
There's an old Accuson in the lab that i recently fixed up for the odd bit of echocardiography, complete with about 10 different transducers.
I've got a bit of bike that an aluminium insert has debonded from, i want to have a look to see if it's safe to remove-sandblast-reglue; the main problem is knowing whether it'll come out without ruining the carbon too bad.
So I want to scan this part using the recently fixed ultrasound machine.
First question, for anyone in the know is whether a clinical device can be used to scan carbon.
Second, what frequency range for the transducer do I want?
Third, will normal ultrasound gel (for use on people) do the job?
No direct experience I'm afraid, although I do use an stethoscope to pump my tires up.
Just take it to the x-ray machine at the airport, those folk are usually pretty helpful 😀
Typical freq will be 5 to 10 MHz. Use a well damped broadband transducer in pulse echo mode. I'm assuming that its carbon bonded to alloy. Two options, propergate thru to the back of the alloy or monitor the amplitude of the bondline. If its thin then you will need a high enough freq to resolve the reflection from the back of carbon / front of alloy. Its a huge impedance mismatch so the reflection should be large and get larger over a disbond. I would say a delay line is a must and of course you need to choose the length to avoid multiples. Gel will be fine.
In my experiance consumer carbon products are ultrasonically challanging. Full of voids, attenuative, variable volume fraction and hence velocity and poorly controlled bondline thickness.
I thought CT was the thing for imaging CF? I'd assume (from my inexpert understanding of ultrasound) it won't give you particularly good images as it's too solid and therefore won't transmit the signal all that well.
Andy
I would have to justify using the CT scanner (or X-Ray) but the ultrasound is just sat in the corner, free for anyone to have a play with.
Thanks for the advice. All i need to look at are the edges between the aluminium and the carbon, to see whether it's smooth and will come out or keyed/barbed.
If all you want to do is image the metalic then I would do a simple low Kv X ray. Carbon is virtually transparent to X rays so all you will see is the metallic. Trying to ultrasonically image the shape of the metalic under the carbon will be difficult with all the other variables especially if you suspect the metalic isnt normal to the beam.