- Polymer matrix
- Ceramic matrix
Composites are materials which are composed of fibers embedded in a matrix. The matrix material in powder or liquid form is combined with reinforcing fibers in a mold, where the combination is subjected to heat and pressure to fuse the part together. Different materials can serve as the matrix, including metals, ceramics, and plastics.
The characteristic of composites that makes them most attractive is their ability to provide increased strength and stiffness at smaller weights than would be needed from conventional materials. Weight reduction permits improvements in military and civilian applications.
As an example, composite materials reduce aircraft empty weights and increase fuel fractions, leading to smaller, lower-cost aircraft that use less fuel to perform a given mission. For airliners, this translates into simple economics, leading to overseas sales or purchases. For military aircraft composites reduce weight, and therefore life-cycle cost and fuel usage.
The ability of composites to reduce weight while maintaining strength is a contributor to enhancing national security and warfighting capabilities as well. It allows improvements in global power projection capabilities through the creation of lower-weight equipment.
Europe and Japan are slightly behind the United States in composite technology. The United States pioneered research in polymer matrix composites (PMCs) in the 1960s and continues to lead the world in this technology.