ABSTRACT
Polymer matrix composites (PMCs) are used in many aerospace, automotive, industrial and consumer applications, often competing with other structural materials, such as steels, aluminum alloys, and titanium alloys. The mechanical properties, such as tensile strength and modulus, of a PMC can be altered relatively easily by changing the fiber type, fiber length, and fiber arrangement. The major constituents in a PMC are the fibers and the polymer matrix. Fibers are the principal load-carrying members in a fiber-reinforced composite material. This chapter discusses the general characteristics of glass, carbon, and aramid fibers. The role of the matrix in a PMC is to keep the fibers in place, transfer load among the fibers, and protect them from moisture, chemicals, and other environments. Thermosetting polymers, such as epoxies, are the traditional matrix materials in many high-performance composites, particularly for aerospace applications. Fillers are added in some PMCs to reduce cost and control molding shrinkage.
