Lighter, Stiffer & Stronger: Sandwich Composites

Text & Diagrams by Matthew Ardian 

   

Sandwich panels add a lightweight core in between 2 facesheets to increase bending stiffness. This is captured by the parallel axis theorem. The core takes the majority of the compressive and shear loads, and the facesheets take the planar loads.  

Fiber composites like carbon fiber & fiberglass are especially good for absorbing planar loads due to their high planar and unidirectional strength. They are already are the materials of choice for many high performance structural applications in industries such as spacecraft, aerospace, marine & sports equipment due to their high strength to weight ratio.

So what do you get when you combine both? Extremely high bending stiffness and strength at an extremely light weight.  

Our lab at SUTD uses 2 kinds of core materials in our lab: End grain balsa & Corecork. 

End Grain balsa is 

Corecork is a cork product released by Amorim for composite sandwich usage. It is compatible with hand layup, RTM, vacuum bagging & vacuum infusion. 

Cork is mainly comprised of suberin arranged in a honeycomb cellular structure. This gives it fire and water resistance, as well as good vibrational damping properties. 

Insert end grain balsa pics here.