Static FEA analysis for HDPE plastic

Hi Ladies and Gents,

I have a plastic component that i am trying to see how much it will stretch when i apply 700 pounds of weight to it. I am attaching the result.
Each side of tab(3.33 square inches) recieves 52.25psi bringing the total to 700 pounds.

My questions are rather simple. In real life when I test this in an aparatus i get approximately 1.5" of elongation after 30 seconds of the load applied to it...

Why is solidworks showing me only approximatelly 0.15"??? What am i doing wrong? This is a static simulation if that makes any difference.

Is my material specification wrong?

Thank you for your help!

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