Composites

1. Composites Composites form a class of materials that satisfy such rigid, often contradictory requirements as ensuring minimum construction mass, maximum strength, stiffness, reliability and durability when working under severe loading conditions, including high temperatures and corrosive environments. Various combinations of matrix material and filler make it possible to produce composites with a wide range of characteristics, which can not be achieved in metallic alloys. T\isunitstrength Е\isspecific modulus of elasticity

2. Composites are systems consisting of two or more dissimilar (heterogeneous) components having interfaces between them.A component that is continuous throughout the volume of material, ensuring its solidity, is called a matrix. The components distributed in the matrix are called fillers. According to the type of matrix, composite materials are divided into composites on a polymer, metal and ceramic basis. By the form and structure of the filler, composites are divided into particulate composites(a),fibrous composites(b–d) and lamellar composites(e, f).

3. Carbon fiber-reinforced plastics are composite polymeric materials reinforced with fillers made of carbon fibers in the form of filaments, ribbons, fabrics. Carbon plastics are characterized by low density, high strength, vibration resistance, increased chemical resistance, practically zero coefficient of linear expansion. Carbon plastics are used as structural materials in aerospace engineering, automotive, shipbuilding, mechanical engineering, and medical equipment. Conveyor line robot’s hand made of carbon fiber composite

4. Heat resisting composite with nickel matrix (operating temperature up to 1000-1200 ° C). The filler can be fine powders of thorium dioxide ThO2 and hafnium dioxide HfO2 or tungsten wire. Thus, the introduction of tungsten wire in an alloy of nickel with chromium in an amount of 40 to 70%, makes it possible to increase its heat resistance at 1100 ° C by a factor of two. They are used in aeronautical and space engineering for manufacturing blades of gas turbines, combustion chambers. In the photo: Blades of gas turbines made of nickel composite.

5. Composite materials with boron fibers (boroplastics and boron aluminum) are widely used in aviation, rocketry and space technology for the manufacture of large parts for supersonic airplanes and spacecraft. Modulus of elasticity and heat resistance of boron-aluminum composites are superior those of all high-strength aluminum alloys. Boron softens slightly with increasing temperature, so the composites retain high strength up to 400-500 ° C. High damping capacity of the material ensures vibration resistance of the structures made of it. The composite material BKA-1, containing 50% of continuous high-strength boron fibers in an aluminum matrix has found an industrial application.

6. The use of various composites in the design of the Space Shuttle has reduced its mass by 1402 kg. Such a saving of weight allowed to reduce the cost of bringing the ship into orbit by several million dollars, that in advance paid for the cost of the elements of the construction of these materials. The launch of the reusable space system "Energia-Buran" (the last space project of the USSR)