Carbon Fiber

Carbon Fiber is a composite material made of strands of carbon thread held together with an epoxy laminate.

Carbon Fiber is much, much stiffer than most other materials of the same weight. It also has good impact resistance.

When Carbon Fiber fails, it's usually in a more drastic fashion than metals. As opposed to denting, it typically "shatters" and loses any useful structural strength.

It's hard to make a direct comparison, but I would probably use an approximately .03" thick carbon fiber plate in substitution for .06" lexan, or .016 titanium (disclaimer - I don't have any real basis for this besides what "seems about right" from my experience).

A .06" thick sheet is stiff enough to provide for a very rigid antweight base plate - good for mounting a weapon motor to.

Carbon Fiber is easier to drill than a similar thickness of metal, but is surprisingly hard on tools.

Dragon Plate makes unique carbon fiber plates than sandwiches wood between layers. The advantage is reduced weight and cost while maintaining most of carbon fiber's strength and rigidity.

www.robotcombat.com also supplies carbon fiber sheets.