- Composites can be lighter than metals while maintaining strength in desired directions by not being isotropic. Composites contain two or more materials in different phases. - Common composite manufacturing processes include compression molding, resin transfer molding, hand lay-up, filament winding, and pultrusion. Process depends on fiber length and part geometry. - Fiber reinforcements include fiberglass, carbon fiber, and aramid fibers. Carbon fiber provides very high stiffness while aramid fiber is strong and impact-resistant. Fiber orientation affects composite strength and properties.