Criteria regarding Resin Content

[kilbchoi]

Hi guys,

I am choosing the suitable Glass Fabric product.

I am wondering if there is any criteria regarding the resin
content. As far as I know, roughly 40% is quite standard.
What about 30%? Obviously it can provide better mechanical
properties for stfinness and strength. As far as I know,
the low resin content cause a problem in cocuring with
Honeycomb core but it can be resolved with applying the
adhesive film. Any other criteria which I should take into
consieration ?

Hope to get valualbe comments soon.

Thanks,

Kilbchoi

 

[polymire]

The general wisdom is that if you exceed about 65% fiber volume (35% resin) then the "through thickness" properties will begin to fall, for example Inter-laminar shear strength, impact resistance etc.

for best properties aim for 60% +/-5%

 

[DPM]

The tradeoff are:

Higher resin content usually makes the part easier and more forgiving to make, provides higher peel strength for cocured sandwich strcuture, provides better impact damage toughness, and appear nicer (more glossy finish).

The downsides to higher resin content are the part weighs more, sometimes the excess resin can create a problem if flow cannot be controlled, and the material will cost more per square foot (you buy prepreg by the pound, and more resin means more weight and cost per unit area, with no increase in inplane mechanical properties).