Matter & Energy


Matter is composed of atoms or groups of atoms called molecules. The arrangement of particles in a material depends on the physical state of the substance. In a solid, particles form a compact structure that resists flow. Particles in a liquid have more energy than those in a solid. They can flow past one another, but they remain close. Particles in a gas have the most energy. They move rapidly and are separated from one another by relatively large distances.

Mineral Fibers

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Glass, which is made from silica sand, is the only inorganic (mineral) fiber widely used in commercial applications. There are two main forms of glass fibers: continuous and staple. Continuous glass fiber, which is made by drawing molten glass into threads, is used in textile materials. The use of air, steam, or gas to disrupt the flow of the molten glass stream produces staple fibers. These fibers can be fabricated into mats or into bulk-molding and sheet-molding compounds with the use of resins, or organic binders. Quartz mineral is high-silica, high-purity glass that is good for long-term use at temperatures as high as 1400° C (2552° F).

Since the early 1960s, ceramic fibers such as aluminum oxide, (also called alumina [Al203]), silicon carbide (SiC), and boron carbide (B 4C) have been developed mainly for use in heat-resistant composite materials (see Ceramics). Many components of helicopters, military aircraft, civil aircraft, missiles, and spacecraft, including satellites and space shuttles, are made from these high-strength, lightweight composites.

Fibers of asbestos, formerly used for insulation and fireproofing, were found to be carcinogenic and are no longer used. Thin metal wires are used for the production of gauze. Aluminum fibers coated with plastics possess a bright glitter and are used in decorative yarns.