Experimental Shear Modulus and Poisson Ratio

[Illgresi]

I'm designing a 'thing' for my masters project, which has to be 3D printed. I've designed this in Inventor, but it doesn't have PLA (Polylactic Acid), so I've been using Inventor's PMMA (Perspex) thus far. I want to get more accurate figures, so I've had a 1 cm³ block printed to get an exact density. I'm also printing tensile test specimens so we can get a Young's modulus.

To properly define the material, Inventor needs a shear modulus and the Poisson ration.

In our course we've never determined these experimentally.

So my question is, how do I determine the shear modulus and Poisson ration experimentally?

Thanks in advance!

 

[gtoguy97]

The shear modulus and Poisson ratio can be determined experimentally by performing a torsion test and a uniaxial compression test.For the torsion test, you'll need to use a specimen that is cylindrical in shape, with a uniform cross-section throughout its length. The specimen should be mounted between two torque transducers, and then subjected to a series of increasing torques. The torque-twist relationship should then be plotted to determine the shear modulus.For the uniaxial compression test, you'll need to use a specimen that is rectangular in shape, with a uniform cross-section throughout its length. The specimen should be mounted between two force transducers, and then subjected to a series of increasing loads. The load-deformation relationship should then be plotted to determine the Poisson ratio.