Industrial Carbon and Graphite Materials. Группа авторов

Industrial Carbon and Graphite Materials - Группа авторов


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      See: GRAPHITE, RHOMBOHEDRAL GRAPHITE.

      High‐Pressure Graphitization

      Description

      HIGH‐PRESSURE GRAPHITIZATION refers to a solid state transformation of NON‐GRAPHITIC CARBON into GRAPHITE by heat treatment under elevated pressure (e.g. 100–1000 MPa) so that a definitely higher degree of GRAPHITIZATION is achieved at lower temperature and/or for a shorter heat treatment time than in heat treatment of the same NON‐GRAPHITIC material at atmospheric pressure.

      See: GRAPHITE, GRAPHITIZATION, NON‐GRAPHITIC CARBON.

      Description

      HIGHLY ORIENTED PYROLYTIC GRAPHITE (HOPG) is a PYROLYTIC GRAPHITE with an angular spread of the c‐axes of crystallites of less than 1°.

      See: GRAPHITE, PYROLYTIC GRAPHITE.

      Notes

      Commercial HIGHLY ORIENTED PYROLYTIC GRAPHITE is usually produced by stress annealing at approximately 3300 K.

      Isotropic Carbon

      Description

      ISOTROPIC CARBON is a monolithic CARBON MATERIAL without preferred crystallographic orientation of the microstructure.

      See: CARBON MATERIAL.

      Notes

      ISOTROPIC CARBON can also be a GRAPHITE MATERIAL. The isotropy can be gross (bulk), macroscopic, or microscopic depending on the structural level at which isotropy is obtained. This word is widely used today and its meaning covers all the above levels. For example, the aerospace graphites have isotropy built in by random grain orientation. Some NUCLEAR GRAPHITES are isotropic at the crystalline (sub‐grain) level.

      See: GRAPHITE MATERIAL, NUCLEAR GRAPHITE.

      Isotropic Pitch‐Based Carbon Fibers

      Description

      ISOTROPIC PITCH‐BASED CARBON FIBERS are CARBON FIBERS obtained by CARBONIZATION of isotropic pitch fibers after these have been stabilized (i.e. made non‐fusible).

      See: CARBON FIBERS, CARBONIZATION, PITCH‐BASED CARBON FIBERS, STABILIZATION TREATMENT

      Notes

      During fabrication of ISOTROPIC PITCH‐BASED CARBON FIBERS, no means (neither mechanical nor chemical) are applied to achieve preferred orientation of the polyaromatic molecules in the fiber direction. They belong to the CARBON FIBERS TYPE LM (LOW MODULUS), and because of the relatively low values of strength and Young’s modulus, this PITCH‐BASED CARBON FIBER type is not used for high‐performance reinforcement purposes.

      See: CARBON FIBERS TYPE LM, PITCH‐BASED CARBON FIBERS.

      Description

      LAMP BLACK is a special type of CARBON BLACK produced by incomplete combustion of a fuel, rich in aromatics that are burned in flat pans. LAMP BLACK is characterized by a relatively broad particle size distribution.

      See: CARBON BLACK.

      Mesogenic Pitch

      Description

      MESOGENIC PITCH is a PITCH with a complex mixture of numerous essentially aromatic hydrocarbons. It does not contain anisotropic particles detectable by optical microscopy. MESOGENIC PITCH is low in quinoline‐insoluble fractions and capable of transforming into MESOPHASE PITCH during continuous heat treatment above 750 K by the formation of optically detectable CARBONACEOUS MESOPHASE.

      See: CARBONACEOUS MESOPHASE, MESOPHASE PITCH, PITCH.

      Mesophase Pitch

      Description

      MESOPHASE PITCH is a PITCH with a complex mixture of numerous essentially aromatic hydrocarbons containing anisotropic liquid‐crystalline particles (CARBONACEOUS MESOPHASE) detectable by optical microscopy and capable of coalescence into the BULK MESOPHASE.

      See: BULK MESOPHASE, CARBONACEOUS MESOPHASE, MESOGENIC PITCH, PITCH.

      Notes

      The CARBONACEOUS MESOPHASE particles are formed from the aromatics of high molecular mass in MESOGENIC PITCH, which have not yet been aggregated to particles detectable by optical microscopy within the apparently isotropic PITCH matrix. The CARBONACEOUS MESOPHASE is insoluble in quinoline and pyridine, but the amount of mesophase measured from microscopical observation appears somewhat higher because parts of the CARBONACEOUS MESOPHASE can be extracted by the solvents.

      See: CARBONACEOUS MESOPHASE, MESOGENIC PITCH, PITCH.

      Mesophase Pitch‐Based Carbon Fibers

      Description

      MESOPHASE PITCH‐BASED CARBON FIBERS (MPP‐BASED CARBON FIBERS) are CARBON FIBERS obtained from MESOGENIC PITCH after it has been transformed into MESOPHASE PITCH (MPP) at least during the process of spinning and after the spun MESOPHASE PITCH fibers have been made non‐fusible (stabilized) and carbonized.

      See: CARBON FIBERS, MESOGENIC PITCH, MESOPHASE PITCH, PITCH, PITCH‐BASED CARBON FIBERS.

      Description

      METALLURGICAL COKE is produced by CARBONIZATION of coals or coal blends at temperatures up to 1400 K to produce a macroporous CARBON MATERIAL of high strength and relatively large lump size.

      See: CARBON MATERIAL, CARBONIZATION.

      Notes

      METALLURGICAL COKE must have high strength to support heavy loads in the blast furnace without disintegration. METALLURGICAL COKE is also used as FILLER COKE for POLYGRANULAR CARBON products.

      See: FILLER COKE, POLYGRANULAR CARBON.

      Microporous Carbon

      Description

      MICROPOROUS CARBON is a porous CARBON MATERIAL, usually a CHAR or CARBON FIBERS, which may or may not have been subjected to an activation process to increase its adsorptive properties. A MICROPOROUS CARBON is considered to have a major part of its porosity in pores of less than 2 nm width and to exhibit apparent surface areas usually higher


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