Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

FKM Modulus

Status
Not open for further replies.

dgallup

Automotive
Joined
May 9, 2003
Messages
4,715
Location
US
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.
 
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
 
Thanks flexibot, that's better data than I've found. Do you agree that Poison's ratio is 0.5?
 
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.

 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top