# Carbon fibre lamina properties

Discussion in 'Materials' started by nemo, Jan 12, 2011.

1. Joined: Apr 2002
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### nemoNaval Architect

Hello,
when I have to do composite structual calculations, usually I start from given mechanical properties of the laminas in order to obtain the laminate properties.
This time I've been given the properties of the naked fibers (Toray T700) which are used to build the lamina. I need to obtain the elastic modulus of a unidirectional 1000 g/sq.m and of a biax +-45° 400 g/sq.m.
How should I do that? Do I have to go into micromechanics?

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### rxcompositeSenior Member

I think it is the only way to go as it is more accurate. The strength of the laminate is dependent on the matrix you will be using so you have to combine it with the fiber (T700 in this case).

Attached is the formula (from Composites Design Guide) and might help. This applies only in the longitudinal direction of the fibers so you have to calculate for reduction of strength for any deviation in angle. A different formula is used for Uni and WR. For the modulus, you can use the rule of mixture and apply the same axial deviation formula by substituting modulus for strength.

Rx

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• ###### Strength.jpg
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3. Joined: Oct 2004
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### HermanSenior Member

Here some data.

#### Attached Files:

• ###### carbon properties.pdf
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