Material properties relevant to vibrational dampening

[bahamonm]

Anyone, I am trying to design an experiment(DOE)which will resolve the key material properties and optimal levels to dampen the mechanical vibrations transmitted from a receiver to the casing of an In-The-Ear hearing instrument. I am primarily concerned w/ visco-elastic materials which can be die-cut to serve as "sleeves" around transducers which typically measure in the vicinity of .25"x.17"x.12". I've researched a little bit and have noted parameters such as :dynamic modulus, damping coefficients, etc...: however, I am concerned that most of these parameters are not well represented on your "run of the mill" tech sheet. I am an IE by training and consequently do not have any appreciable depth in the field of acoustics. Any help would be greatly appreciated.

 

[GregLocock]

The problem with damping, in particular, is that the answer you get very much depends on the test method you use.

Also, the damping factor varies substantially with frequency, temperature, geometry etc etc.

If you have $$$ then Anatrol are often a good source of data and expertise on damping materials.

My approach would be to select a standard test methodology that closely approximates your actual design condition, and then start phoning suppliers and getting samples, and testing them yourself.

I've also found 3M will often take an interest in odd applications.



Cheers

Greg Locock

 

[sms]

Go look at what is on the market. Ultimate ears makes a great system for musicians to use as monitors during live performance. You could see how they approched the problem...

http://www.ultimateears.com/

 

[JoeUSA]

Try calling EAR Specialty Composites in Indianapolis. They manufacture acoustic isolation and damping materials for all kinds of applications - web site is

http://www.earsc.com.

They have applications engineers who might be helpful.