The biggest advantage of boron fibers is their high compressive strength. In comparison to fiberglass-epoxy, this means that there can be over three times less graphite fibers while retaining the same strength in the composite, a considerable weight saving. Composites are being used regularly in today s society. Fifty percent of the Harrier VTOL aircraft is graphite fiber-epoxy composite. Composites, as great as they are for aerospace applications, have other applications besides aircraft structures.
Steel belted tires are steel fibers in a rubber matrix.
Reinforced concrete is steel rods in a concrete matrix. Bulletproof vests and the helmets that the U.S. Army uses are made with Kevlar. Kevlar is an extremely high modulus aramid fiber composite with high resistance to chemical and heat degradation, although it is not suited to deal with high compressive stresses. There has also been an increased use of composites in car manufacturing over the years. Unfortunately, this isn t a peaches and cream story for composites.