Hyperelastic Materials

Greetings,

I'm conducting a simple shear test (single lap joint) between aluminum bonded with 3M adhesive. 

Adhesive material is 3M VHB 4930 adhesive (acrylic)

Result obtains = 

Load vs Displacement Curve

True Stress vs Stretch Ratio

From the literature, mostly they used Yeoh model for 3M adhesive (Modeling and simulation of dielectric elastomer actuators,M.Wissler 2005).

The material constant for C10, C20, C30 I get from the curve fitting equation from the True Stress vs Stretch Ratio.

Hello,

I am working on my master's thesis. I have to find best fitting hyperelastic material model for simple shear test.

My task is to find most proper material model which will fit my laboratory test data. I have conducted the "single lap test" on bricks, using polymer PS.

Hello,

I am working on testing of rubber couplings. I have a problem, that while doing torsional test of the coupling, we are getting different values of stiffness with change in time. Even if we do the testing and then take a small break of 10-20 minutes, then also after 20 minutes I am getting different values.

My question is, that is it possible because of Mullin effect? If so, How can we check that the rubber couplings that I have are filled or not( one piece rubber or filler with some other elastomer)?