Measuring Elasticity of an annular disc

[umermajid]

I have an annular disc that looks like the picture attached.

I need to get the elasticity of the material, since I don't have any information on it. Does anyone have any suggestions on how I can calculate the elasticity?

Maybe I can get a force/displacement curve by bending the disc (held at the center)? I have equipment to do that. But how can I use that information to get the modulus?

Any help will be appreciated

Thanks & Regards,

Umer

 

[EdStainless]

acoustic resonance.
Though without a regular size (uniform cross section) it may be an estimate at best.
What is the material? Metal, plastic, ceramic????
You may be able to figure this out by process of elimination.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

 

[umermajid]

Hi,

thanks for your response.

The material is a kind of fibre-glass. I don't really need an accurate measurement. Just an estimate will do.

 

[cloa]

I assume elastic modulus is what you want.
You could try measuring the speed of speed in the medium but it would be hideously difficult and complex with that shape and the complex nature of the material.

http://en.wikipedia.org/wiki/Speed_of_sound

 

[RPstress]

If you can provide more information about the material (the nature of the glass fibres, such as short fibres or woven cloth, and the nature of the matrix, such as as a thermoplastic or an elastomer) then an estimate of the Young's modulus of similar materials can be provided.

Failing that, applying a controlled load in a certain way could be modeled (perhaps an annular out-of-plane load with the disc held reasonably rigidly at the center). Modeling could be done either by finite element analysis or simple approximate formulas such as those for circular plates in 'Roark's Formulas for Stress and Strain.'

It depends a bit on what you want the elasticity/modulus number(s) for.

 

[MintJulep]

Are you interested in the behavior of the part, or the properties of the material?

 

[metman]

Do you have access to a large weight? Load it in the position shown. Measure OAH before and after loading. Calculate the cross sectional area and moment of inertia and then calculate stress and modulus.