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      01-08-2013, 07:32 AM   #8
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Originally Posted by aka_phox View Post
So its safe to buy a bumper made of this material?
The material alone won't let you know whether it is safe enough. Other factors include the thickness and where that thickness is located. Reinforcements of other materials at strategic locations may also be necessary. A lot of people still treat materials like carbon fiber as a "black aluminum," which is definitely not the case. While a discontinuous chopped fiber or whisker reinforced plastic may result in a quasi-isotropic structure, meaning the material properties are roughly the same in and around the X, Y, and Z axis' similar to metal, the properties of the plastic will not be adequate for high local stresses of joints and attachments. It is even worse with continuous reinforced composites (most people recognize these as the ones with a weave, but the fibers may be aligned in the same direction, which happens to be more efficient for stresses in that particular orientation). But continuously reinforced composites are really only good for transfering of shear load through the structure, and are not at all appropriate for mounting of fasteners (there should be an isotropic reinforcement at all of these locations) and need special design considerations at joints. Also, materials such as carbon and aluminum are at opposite ends of the galvanic scale and need a galvanic barrier, such as fiberglass, otherwise the materials will have signifcant corrosion in as little as 2 weeks.

So basically, ask around about the reputation of the company to see if they have quality products