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Composite material

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A composite material is a substance created by combining two or more constituent materials. These components possess notably dissimilar chemical or physical properties. When they are merged, they form a new structure with properties different from the individual parts.

Composite 3d
Composite 3d

Importantly, the elements remain separate and distinct within the finished structure. This characteristic distinguishes a composite from a simple mixture or a solid solution. Composites are vital because they can be lighter, stronger, or more durable than common materials.

Engineered composites typically rely on a two-part system consisting of a matrix and a filler. The matrix acts as a binding agent that holds the structure together. The filler, which can be particulates or fibers, provides the substance and strength.

Concrete aggregate grinding
Concrete aggregate grinding

For example, fiberglass uses small glass fibers embedded within a polymeric material. The glass fibers are stiff and strong but brittle. The polymer is ductile and flexible but relatively weak. Together, they create a material that is strong, stiff, and ductile.

Cfaser haarrp
Cfaser haarrp

There are several distinct types of composite structures used in science and industry. Composite laminates consist of more than one distinct layer. Sandwich-structured composites use two thin, stiff skins attached to a thick, lightweight core.

Glare honeycomb
Glare honeycomb

This design provides high bending stiffness with very low density. Other types include metal matrix composites (MMC) and ceramic matrix composites (CMC). Ceramic matrix composites are specifically built to improve fracture toughness rather than just strength. Some high-performance versions use shape-memory polymer resins. These can be manipulated into new shapes when heated above an activation temperature.

Humanity has used composites for thousands of years. The earliest examples were bricks made from a combination of straw and mud. Wattle and daub may be the oldest composites, dating back over 6,000 years. Around 3400 BC, Ancient Mesopotamians created plywood by gluing wood at different angles. This process provides better properties than natural wood alone.

Spruce plywood
Spruce plywood

In 1935, Al Simison and Arthur D. Little developed the first artificial fiber-reinforced plastic. They combined glass fiber and bakelite at the Owens Corning Company.

Concrete is the most common artificial composite material produced today. Approximately 7.5 billion cubic meters of concrete are manufactured each year. It consists of a cement matrix holding loose stones, known as construction aggregate. While concrete resists large compressive forces, it is susceptible to tensile loading, or being stretched. To solve this, engineers create reinforced concrete by adding steel bars. These bars can resist the high stretching forces that would otherwise crack the concrete.

Advanced composites are essential for modern high-performance technology. Carbon-fiber-reinforced polymers are used extensively in the aerospace industry. The wings and fuselages of the Boeing 787 and Airbus A350 are composed largely of composites.

Cfk heli slw
Cfk heli slw

In space exploration, carbon composites are used for launch vehicle heat shields and solar panel substrates. They are also used in antenna reflectors and payload adapters. Even in sports, composites are the most common material for hockey sticks and are used in fishing rods and baseball bats.

Composites also appear in specialized automotive and military applications. High-density composites, sometimes called "high gravity compounds," can reach densities of 11 g/cm3. These can replace hazardous materials like lead for weighting or radiation shielding. In the military, Chobham armor is a specialized composite used for protection. Even everyday items like automobile tires are particulate composites. These materials connect various fields, from orthopedic surgery to deep-sea construction, by providing tailored solutions for specific physical challenges.

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🖼️ Images & Media (10)
File:Composite 3d.png
Composite 3d.png
File:Concrete aggregate grinding.JPG
Concrete aggregate grinding.JPG
File:Cfaser_haarrp.jpg
Cfaser_haarrp.jpg
File:Glare honeycomb.jpg
Glare honeycomb.jpg
File:Spruce plywood.JPG
Spruce plywood.JPG
File:Cfk heli slw.jpg
Cfk heli slw.jpg
File:Composite elastic modulus.svg
Composite elastic modulus.svg
File:Isostress and isostrain conditions for composite materials.gif
Isostress and isostrain conditions for...
File:Transform coordinate system.png
Transform coordinate system.png
File:Composite Strength as a Function of Fiber Misalignment.png
Composite Strength as a Function of Fiber...
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