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Is it possible to reach a modulus of elasticity 800 ksi for pultrusion

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jgpower

Structural
Nov 8, 2006
8
US
Hi everyone,

Is it possible to reach a modulus of elasticity 800 ksi using common glass fibers such as E glass, R glass or S glass, not carbon fibers? I am looking for a composite I profile instead of aluminum I profile within some limits on dimensions of the I section. I need a high modulus because of deflection limit.

Any reply is much appreciated.
 
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I have no direct knowledge of properties from pultruded materials but I think we can still make a fair guess on the answer to your question. The modulus of a composite is dominated by the glass fiber, not the polymer because the fiber has a far higher modulus. So, I went here ( and searched for the mechanical properties of a typical polymer (PBT) containing glass fiber. The result was:

PBT 10 weight % GF 725 ksi
PBT 20 weight % GF 1200 ksi

So the answer is that if your pultruded material contains 10-20 weight % glass fiber and the fiber has retained some decent length (not crushed too finely) then you should reach the value you want.
 
I'm a little rusty here, but if volume fraction fibers = .5, then (.5 x 12,000 ksi + .5 x 400 ksi) = 800 ksi. So using a resin of modulus 400 ksi and a vf = .5 you should be good to go.
 
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