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FKM Modulus

FKM Modulus

FKM Modulus

(OP)
I'm looking for appropriate mechanical properties for fluorocarbon materials.  I'm pretty certain Poison's ratio is very close to 0.5.  I'm having a much harder time coming up with Young's Modulus.

The only values I've found are 6 MPa for a "typical" ~70 durometer material and 14 MPa for a "high modulus" material of unspecified durometer.

Any hard data would be appreciated.

RE: FKM Modulus

I found this information trust it is of some help.

Hardness versus Modulus
There is a rough relationship between the Young's modulus of a material and its hardness,as measured by a Shore durometer. There are several Shore 'scales' for hardness. The one normally used for measuring the hardness of soft materials like rubber is the Shore A scale. The relationship between Shore A hardness and the Young's modulus is listed in
Table 1.
Shore A    Modulus(MPA)
10            0.27
20            0.61
30            0.97
40            1.54
50            2.45
60            3.45
70            5.47
80            8.68
Table 1. Relationship between Young's modulus and the Shore A hardness scale.
From http://www.pspglobal.com/properties-hardness.html

RE: FKM Modulus

(OP)
Thanks flexibot, that's better data than I've found.  Do you agree that Poison's ratio is 0.5?

RE: FKM Modulus

Looks like it. this is from the same site.

Incompressibility

A material is incompressible if it exhibits zero volumetric change (isochoric) under hydrostatic pressure. Theoretically, Poisson's ratio is exactly one-half (0.5) and the bulk modulus is infinite (and det f = 1).

Near incompressibility means that Poisson's ratio is slightly less than 0.5.

 

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