What Are Composites?
Composites are engineered products made from two or more different materials. A composite product provides a designed solution that surpasses the performance of the starting materials. While there are many variations of composites, the most common engineered composite materials are fiber reinforced polymers (FRP).
Where are composites found?
Composites are used to raise performance levels, address traditional material design limitations, and enable the development of new product solutions. Composite materials are found in many of the products used in our daily lives, such as cars and trucks, bath tubs and counter tops, boats and windmills. Composites are also used in many critical industrial, infrastructure, aerospace, and military applications.
What are composites made from?
The term composite can describe many types of engineered materials, but the most common engineered composite materials are fiber reinforced polymers (FRP). FRP is often comprised of a reinforcing fiber in a polymer matrix.
- The reinforcing fiber is commonly glass fiber, although high strength aramids, plant based fibers and carbon fibers are used in some applications.
- The polymer matrix is typically a thermosetting binder resin. Polyester, vinyl ester, and epoxy chemistries are the most predominately utilized binders. Polymer selection is driven by end use application characteristics, such as corrosion considerations, cosmetic requirements, operating temperatures, and fabrication requirements.
- Pigment, filler and granule materials can also be used to modify cost, performance and appearance characteristics of the composite part.
How are composite products made? To form a composite part, the liquid polymer binder resin is combined with the fiber and filler materials. The polymer is then converted from a liquid to a solid during a heat and chemistry driven molding process, encapsulating the fibers and fillers into a specific shape. There are many processes available for fabricating composite parts. The fabrication methods range from very simple and low cost direct molding operations to complex processes and equipment operations. The process selected to fabricate the composite part is dependent upon factors such as the quantity of parts to be produced, the design requirements, part complexity and surface appearance.