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jalatty
13th Dec '10, 18:28
Hello,

I am trying to find a good source for elastomer material properties. I am particularly looking for Mooney Rivlin constants for some polyurethanes. Anyone doing analysis of polymers out there?

Thanks,

Aaron

DanStro
13th Dec '10, 21:29
I don't know if they have the constants for your material but www.polymerfem.com (http://www.polymerfem.com) is pretty active and has a lot of good info on it.

HTH,
Dan

jalatty
14th Dec '10, 13:21
Hi Dan.

Thanks for the link. I have been there before and didn't even think of checking it out.

Aaron

LinkedIn Gopher
14th Dec '10, 17:41
I have done a bit of this kind of analysis recently, with fluoro-elastomers. I presume you are doing FEA. The data you need is not easy to come by, as it is necessary to perform a number of separate mechanical tests to identify the constants accurately, and the material providers appear unwilling or unable to do them themselves!

There are some numbers available in this presentation: http://www.midwest-ansys-ug.com/051805_ ... erials.pdf (http://www.midwest-ansys-ug.com/051805_presentations/ANSYS%20Users%20Group_Hyperelastic%20Materials.pdf ), but, as the authors say, you should use them with great care as they are not generally applicable to all elastomers. They might be enough to get you started though.
Source (http://www.linkedin.com/groupItem?view=&gid=2666729&type=news&item=290744303&goback=.gmp_2666729)

jalatty
14th Dec '10, 18:03
This is a good document. Thanks. Yes, I am modelling a structure in FEA. I ended up using some constants from another similar material that we had used on another project. I am only trying to model the behaviour at this stage so it is sufficient for my purposes. If the project gets the go-ahead, we will probably have to get test data.

My FEA package supports Mooney-Rivlin and Neo-Hookean models but these are only as good as the data you input.....and the assumptions you make in the rest of the model of course!

Mekanimo
15th Mar '13, 22:21
I know it's too late for that but I'm currently involved in simulation of polyurethane reinforced model, I used c1=0.7 and c10=1.1 , the following equation is relating both constants to elastic modulus ; E=6(c10+c1) ; if you have E you can presume that c1=1/4 c10 roughly .

If you reached better solutions so far please share :D