Related Pages. Unlike the thermosets, the thermoplastics can usually be reheated and reformed into another shape, if desired. Typically, heat and pressure are used to shape and "cure" the mixture into a finished part. In high concentrations, narcosis is produced with symptoms of headache, nausea, light-headedness, vomiting, dizziness, incoordination, and unconsciousness. Water jet A high-pressure stream of water used for cutting organic composites. Many of the materials, particularly the resins, curing agents, and fibers, present a potential dermal-exposure hazard. Lap joint A joint made by bonding overlapped portions of two adherends. Polymer-matrix composites manufacturing is a multibillion dollar industry in the U.S. and one of the few in which the U.S. is conceded to be slightly more advanced than competitors abroad. The continuous cured part, usually a rod or similar shape, is then cut to the desired length (Figure III:1-7). Also called resole. Practically all glass fibers for composite reinforcement are greater than six microns in diameter. Washington, DC 20210
Release film An impermeable film layer that does not bond to the composite during cure. 1: Composites. These include aliphatic and cycloaliphatic amines, polyaminoamides, amides, and anhydrides. Many manufacturers have replaced the ketones with the above hydrocarbon solvents to reduce the risk of flammability. It is made with stronger yarns in a tighter construction than the body of the fabric to prevent raveling. Release agents Materials that are used to prevent cured matrix material from bonding to tooling. Damping Diminishing the intensity of vibrations. Breather A loosely woven material that does not come in contact with the resin but serves as a continuous vacuum path over a part in production. Wrinkle An imperfection in the surface of a laminate that looks like a crease or fold in one of the outer layers; it occurs in vacuum bag molding due to improper placement of the bag. Do not weld, flame cut metal or use naked flames in vicinity or products. The basic epoxy compounds most commonly used in industry are the reaction product of epichlorohydrin and bisphenol-A. The retina of the eye might be damaged not only by direct contact but also from MDA absorbed through ingestion. in process equipment containers (tanks, reactors, molds, etc.). Heat-distortion temperature Temperature at which a test bar deflects a certain amount under specified temperature and a stated load. However, due to the same properties epoxy products are a notorious cause of allergic skin disease among workers. The principal hazards of carbon-fiber handling are mechanical irritation and abrasion similar to that of glass fibers. Van Nostrand Reinhold Co., New York: 1982. These and the other processes are discussed in more detail in. Fiber placement A continuous process for fabricating composite shapes with complex contours and/or cutouts by means of a device that lays preimpregnated fibers (in tow form) onto a nonuniform mandrel or tool. 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