Molding of graphite

Iron/ carbon alloy, poured as a hot molten liquid into a mold. Usually produced as either gray iron (where flakes of graphite are embedded in an iron matrix) or nodular iron (spheroids of graphite in the matrix). 

Metal molds and cores are used in permanent mold casting. The process works best in continuous operation so that the mold temperature can be maintained within a fixed operating range. The operating temperature of the mold is one of the most important factors in successful permanent mold casting. Mold cavities are machined from solid blocks of graphite. Mold life is the major cost factor in permanent mold casting. 

A thin molding of an acetylene-terminated phenylquinoxaline, fabricated by compression molding at 316°C for 26 hr and at 371°C for 5 hr, gave tensile strength of 103 MPa (15,000 psi), tensile modulus of 2.62 GPa (380,000 psi) and elongation of 5% (46). Preliminary unidirectional graphite fiber laminate properties are reported in Table VI. 

Plugs for graphite bridge initiators are made by molding the plastic about a twisted pair of enameled wires, and thea grinding the surface clean, bis ieaves a plastic surface with two metal islands separated by twice the thickness of the enamel. A droplet of colloidal suspension of graphite in water is applied over the point of closest approach of these islands to dry. Since both resistance... 

The Li-Loos intimate contact model was verified for compression molded unidirectional graphite-polysulfone and graphite-PEEK (APC-2) laminae and graphite-PEEK (APC-2) cross-ply laminates. The degrees of intimate contact of the unidirectional and cross-ply specimens were measured by optical microscopy and scanning acoustic microscopy, respectively. The predicted degrees of intimate contact agreed well with the measured values for both the unidirectional and cross-ply specimens processed at different temperature and pressures. 

Electroforming. The reproduction of an object or a pattern by electro deposition (See under Electrochemistry). A mold of the object to be reproduced is made in a soft metal or in wax (by impression). The non-conductor mold surface is made conductive by coating with graphite. Some suitable metal is then deposited electro lyrically on the mold surface. This mold is then (in most cases) a negative of the object to be produced. Most extensive use is in the phonograph record industry Ref GondChemDicc (1961), 434-R... 

None of these waxes, including the standard, Staiiolind 170/5, was entirely satisfactory. The addition of graphite to the compns, the use of some mold release compds, and a change to a chromium plated punch did not improve the pelleting characteristics... 

ELECTROFORMING. The electrolytic depositing of metal upon a conducting mold to make a desired metal object, such as precision tubing or medals. The mold is often of graphite-coated wax. so that it cun be removed by melting. See also Electroplating. 

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