Vibration Absorption

Hi all

I would like to know what methods / materials you are using to vibration absocion in your composite parts (specifically in panels).
What would be the most effective methods?

I’m testing hybrid woven kevlar / carbon with apoximado vf 50%, standard lamination epoxy resin. It’s work but I would like make it better if possible
Are there special resins for abosrción vibration? I have read about viscoelastic matrices, but not if this really is a noticeable difference.

Regards and thanks

Well perhaps the most effective method for panels is to use a core material. Is vibrational damping your priority over mechanical performance?

I need a supporting point rigid/solid, application will be used to absorve the vibrations transmitted from the road.

I could for example, change in the support area 10mm foam with a 10mm layer of Kevlar if this would improve the absorption of vibrations, but maybe there are better options , I also could change the core material in that area, if that gives better results. I’m open to suggestions.

Best regards

Flax fibre is great for absorbing some vibration.

I’m looking in to other core materials/layup schedules as well, and integrating the stringer (more flax, and carbon instead of glass). But I have to earn some money first :stuck_out_tongue:

Hi Susho, nice deck , I had not heard of the Flax fiber for vibration absorption , but this appear be used also, for example, I saw that flax fiber is used to make bicycle frames in order to increase comfort, but the question is whether works better than Kevlar. I guess it also depends on the frequency of the vibrations.

cloth seems difficult to achieve and therefore probably pretty expensive also.

Where could buy?
Do you recommend use it instead of kevlar?
Is it really necessary using a complete stringer for vibration?
Don’t could work with only layers under trucks?

Loaded is using UHMW on the bottom layer of their chubby unicorn to absorb high frequency vibrations, I wonder if it work well
http://www.loadedboards.com/boards/chubbyunicorn/

Regards

So am I about the loaded board. Basically the more flax is in the composite, the more vibrations would be damped. EU suppliers are MCtechnics in belgium (dry fibres), Amber composites(prepregs) and lineo, belgium, both prepregs and dry fibres. I have a doc. From lineo in which different materials are compered in relation to dampening of vibrations.
Price is comparable to carbon, to a bit less on dry multiaxials.
And it is a lot nicer to work with than kevlar. The lineo flax is quite waterproof too, don’t know about the others.

And no, you don’t need a stringer. I use it as a leaf spring, to dampen some bumps too :slight_smile:

cork core is amazing dampener. Someone here just did a long term study on sandwich panels, and cork won.

Ah,very nice! you could use a combination then of a number of materials as suggested. Kevlar is likely to be useful as mentioned. Perhaps a combination of Kevlar, flax and core - worth investigating anyway.
Flax is also available from Composites Evolution
http://www.compositesevolution.com/Products/Biotex/tabid/95/Default.aspx

If, combination could be an option, maybe different materials offer great absorption capacity at different frequencies, if you mix all of them you could take in all spectrum possible, however flax seems to always win, at high and low frecuecias, however these data may be slightly biased by the interests of the manufacturer … really there are poor information here:

http://www.lineo.eu/
(click over presesentantion Commercial PDF)

http://www.lineo.eu/ #! products
PDF this also

Are these the document you were talking susho?

here is sold retail linen
http://www.viral-surf.com/shaper/es/otras-fibras/2033-ud-lin-tisse-190-gr-m-largeur-100-cm.html

Respect cork core, It could work great, however, for this aplication, to apply directly under trucks, maybe It haven’t the compresive strength necessary to get expectatives, but It could be good option if it’s applied for another form.
I would like to see study on sandwich panels that riff42 mention .
Regards