Composites and composite materials usually consist of a matrix and a dispersed, fibrous or continuous second phase. There are three basic types of composites and composite materials: polymer matrix composites (PMC), ceramic matrix composites (CMC), and metal matrix composites (MMC). Most industrial composites use a resin system, a catalyst or curing agent, and fiber reinforcements that strengthen finished parts. Advanced composites use high-performance resin systems and high-strength, high-stiffness fiber reinforcements. In some cases, an advanced composite or advanced composite material provides electrical properties such as insulation or conductance.
Composites and composite materials are formed through a variety of processes. Examples include resin formulation, solution prepegging, wet filament winding, automated tape lay-up, resin transfer molding, pultrusion, and injection molding. Resin formulation consists of mixing epoxy or other resins with additives such as curing agents or accelerators to achieve specific performance parameters. Prepegging involves the application of formulated resin products to a reinforcement material such as carbon, fiberglass, aramid fiber or cloth. Wet filament winding draws continuous fiber reinforcement materials through a container of resin mixture. Automated tape lay-up feeds a prepeg tape material through an automated tape machine. Resin transfer molding is used to join parts with two smooth surfaces. Pultrusion pulls continuous roving strands from a creel through a strand-tensioning device into a resin bath. Injection molding, one of the oldest methods for producing composites and composite materials, is usually automated.
Composite material suppliers are located across the United States and around the world. They differ in terms of capabilities, approvals and certifications, and markets served. Industrial composites and composite materials are used in consumer products, piping, athletic equipment and construction applications. Aluminum composite materials, composite building materials, and composite roofing materials are commonly available. Some composite material suppliers specialize in advanced composites and composite materials for military and aerospace applications.