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Can somebody help me establish the material properties of fiberglass

Can somebody help me establish the material properties of fiberglass

Can somebody help me establish the material properties of fiberglass

(OP)
I am doing an FEA analysis with Pro/Engineer Mechanica of a linkage arm that is made out of fiberglass (Generic E-glass/epoxy Unidirectional Prepreg). When assigning the material of the part in Pro Engineer, I need to input the following:

E1, E2, E3, G12, G13, G23, Nu21, Nu31, and Nu32.

Can somebody please help me with what values to use. The fiber will run along the X (1) direction. The Y (2) direction will be transverse to the fiber. The thru material direction will than be the Z (3) direction.

I have found data that provides the following about Generic E-glass/epoxy Unidirectional Prepreg:

E1 = 39 GPA,  E2 = 8.6 GPA,  G12 = 3.8 GPA,  Nu12 = .28

However, I just don't know if I am correctly converting the rest of the values (E3, G13, G23, Nu21, Nu31, and Nu32) from these values.

Thanks,
Justin
 

RE: Can somebody help me establish the material properties of fiberglass

As a rough estimate for uni tape:

nu21 = (E2/E1)*nu12
E3 = E2
G13 = G12
G23 = 0.67*G12
nu31 = nu21
nu32 = 0.45


 

RE: Can somebody help me establish the material properties of fiberglass

(OP)
Thanks SWComposites for quick response and good answer.

Just out of curiosity, where did you get nu32 = .45 ?

Also, how did you know that G23 = .67*G12?

I have read your previous posts and had seen you answer G23=.67*G12 before. Is that just something proven from experience in the field?

Finally, do you feel the values I had posted above:
E1 = 39 GPA,  E2 = 8.6 GPA,  G12 = 3.8 GPA,  Nu12 = .28
are a good estimation values for "Generic E-glass/epoxy Unidirectional Prepreg"?

Thanks again,
Justin




 

RE: Can somebody help me establish the material properties of fiberglass

Your values for uni f/g tape properties are reasonable.

There is some f/g data in Mil-Handbook-17 Volume 2; a copy can be purchased from ASTM, www.astm.org.  There is also f/g data in various textbooks and online in vendor data sheets.  Check the Cytec, Hexcel, ACG, Nelcote, etc websites.

My thru-thickness estimates are based on some carbon fiber/epoxy data in Mil-Handbook-17 and some proprietary data.

Steve
 

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