Thin Ply Technology, any specialist here?

Hi,
With the following link, you can find an interesting article which states that infused TPT using C-Ply with shallow angle (20°) provides similar result than autoclave with classic prepeg laminate(90°/45°/0°....)

Bi-angle fabrics find first commercial application https://www.compositesworld.com/articles/bi-angle-fabrics-find-first-commercial-application

Well it seems very attractive, but the bicycle application as mentionned at the end of this document,
mentions C-Ply made with 0° and 45°.

While "shallow angle" (20°) is presented as the main advantage of the C-Ply technology.

I am a bit confused with this issue, so if anybody can provide insight, you are welcome

Cheers

Erwan

 

I am not an expert but I think what is happening is, standard fabric 0/90/+45/-45 is designed so that its properties vertically and horizontally are the same.

In an engineering application often the stresses in one direction are different to those at right angles, so having the properties the same means the fibres in the less stressed direction are over-designed.
The C-ply configuration shown in the picture has 0/+45/-45/0 meaning the strength and stiffness up and down is much greater than side to side to match the different needs.

Various shallow angles had been tested and in this instance for the bike frame 45 was found to be best.
For other cases eg “An unbalanced 0°/25° layup, for example, can take advantage of shear coupling to reduce bending and twisting in wing-type structures or wind blades.”

The article is dated 2012, there are probably further developments.

 

Thank you Latestarter for taking time to read and write.

The best thing for me is to take take time to make some research and try to understand in depth this shallow angle applications.
C-Ply is a biaxial thin ply for industrial applications in order to cut off labor time for similar mechanical quality.
So I guess, that even if used "traditionnaly ie:90°/45°/0° ) thin plys are likely to achieve good results without autoclave, that remains very attractive.
Also, what is interesting with thin ply is the technology used to flatten carbon tows to get the thin plys.

Cheers

Erwan