Composite Strengths

General Composites Discussions Engineering Talk
#1

Hi all,

As far I understand, the lesser the resin, and more the fiber (that is higher fiber to resin ratio)

But then there has to be an optimum Fiber to resin volume ratio depending on the GSM, the Weave etc?

I found a chart on fiberglast.

What if we are using Fibers from one vendor and resin from a different one. Also when we talk about best properties , it means all stiffness and strength criteria (shear, tensile, compressive) etc.
I just want to know whose responsibility is it to maintain charts for ideal fiber to resin ratio for different properties. If it is of the end users, how does a hobbyist go about doing it compared to say a proper company

#2

Generally a 60/40 resin content is considered ideal.

There are some application where more fiber volume is beneficial. You really shoot for 60/40 but depending on the process, it may vary. That’s the nature of composites.

The ratio is generally the same for the various wovens. Unidirectional is usually drier as the fibers are more densely packed.

#3

Have a look http://www.r-g.de/en/laminate-calculator.html