Industrial Carbon and Graphite Materials. Группа авторов

Industrial Carbon and Graphite Materials - Группа авторов


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> 0.05, where xo is the interatomic distance in the crystalline lattice for the sp2 as well as for the sp3 configuration) occur in such materials, as well as deviations in the bond angles because of the presence of “dangling bonds.”

      The above description of AMORPHOUS CARBON is not applicable to CARBON MATERIALS with two‐dimensional structural elements present in all pyrolysis residues of carbon compounds as polyaromatic layers with a nearly ideal interatomic distance of a = 142 pm and an extension greater than 1000 pm.

      See: CARBON MATERIAL.

      Artificial Graphite

      Description

      The term ARTIFICIAL GRAPHITE is often used in place of SYNTHETIC GRAPHITE.

      See: SYNTHETIC GRAPHITE.

      Notes

      This term is not recommended.

      Baking

      Description

      The process in which the carbonaceous BINDER, usually COAL‐TAR PITCH or PETROLEUM PITCH, as part of a shaped CARBON MIX is converted to CARBON yielding a rigid carbon body by the slow application of heat. The process can take as little as 14 days in coarse‐grained, electrothermic grades (low binder level) and as long as 36 days in ultrafine‐grained, specialty grades (high binder level). The final baking temperature can be in the range of 1100–1500 K, depending on the grade.

      See: BINDER, CARBON, CARBON MIX, COAL‐TAR PITCH, PETROLEUM PITCH.

      Binder

      Description

      A BINDER is usually a COAL‐TAR PITCH or PETROLEUM PITCH (but may include thermosetting resins or MESOPHASE PITCH powders) that, when mixed with a BINDER COKE or a FILLER, constitutes a CARBON MIX. This is used in preparation of the formation of shaped green bodies and subsequently CARBON ARTIFACTS.

      Binder Coke

      Description

      BINDER COKE is a constituent of a carbon (or ceramic) artifact resulting from CAROBONIZATION of the binder during baking.

      See: CARBONIZATION.

      Notes

      PITCHES are mainly used as binders, i.e. as precursors for BINDER COKES, but the term BINDER should include any carbonaceous binder material, for example, thermosetting resins such as poly(furfuryl) alcohol or phenolics and similar compounds, which may form a CHAR during CARBONIZATION.

      See: BINDER, CARBONIZATION, CHAR, PITCH.

      Brooks and Taylor Structure in the Carbonaceous Mesophase

      Description

      The BROOKS AND TAYLOR STRUCTURE IN THE CARBONACEOUS MESOPHASE refers to the structure of the anisotropic spheres that precipitate from isotropic PITCH during pyrolysis. The structure of the spheres consists of a lamellar arrangement of aromatic molecules in parallel layers that are perpendicular to the polar axis of the sphere and are perpendicular to the mesophase–isotropic phase interface.

      See: PITCH.

      Notes

      The term BROOKS AND TAYLOR STRUCTURE is recommended to describe the particular lamellar morphology of the spherules most commonly precipitated from pyrolyzed PITCH. The term honors the workers who first recognized the significance of CARBONACEOUS MESOPHASE to carbon science and technology and who first defined this spherical morphology. The term BROOKS AND TAYLOR STRUCTURE does not cover all structures found in spherical mesophase, because other lamellar arrangements have been observed.

      See: CARBONACEOUS MESOPHASE, PITCH.

      Bulk Mesophase

      Description

      BULK MESOPHASE is a continuous anisotropic phase formed by coalescence of mesophase spheres. BULK MESOPHASE retains fluidity and is deformable in the temperature range up to about 770 K and transforms into GREEN COKE by further loss of hydrogen or low‐molecular‐weight species.

      See: GREEN COKE.

      This BULK MESOPHASE can sometimes be formed directly from the isotropic PITCH without observation of intermediate spheres.

      See: PITCH.

      Calcined Coke

      Description

      CALCINED COKE is a PETROLEUM COKE or COAL‐DERIVED PITCH COKE obtained by heat treatment of GREEN COKE to about 1600 K. It will normally have a hydrogen content of less than 0.1 wt%.

      See: COAL‐DERIVED PITCH COKE, GREEN COKE, PETROLEUM COKE.

      Notes

      CALCINED COKE is the main raw material for the manufacture of POLYGRANULAR CARBON and POLYGRANULAR GRAPHITE products (e.g. CARBON and GRAPHITE ELECTRODES).

      See: CARBON ELECTRODE, GRAPHITE ELECTRODE, POLYGRANULAR CARBON, POLYGRANULAR GRAPHITE.

      Carbon

      Description

      CARBON is the element number 6 of the periodic table of elements (electronic ground state 1s2 2s2 2p2).

      Notes

      For description of the various types of CARBON AS A SOLID, the term CARBON should be used only in combination with an additional noun or a clarifying adjective.

      See: AMORPHOUS CARBON, CARBON FIBERS, CARBON MATERIAL, GLASS‐LIKE CARBON, GRAPHITIC CARBON, NON‐GRAPHITIC CARBON, PYROLYTIC CARBON.

      Carbon Artifact

      Description

      CARBON ARTIFACT means an “artificially produced” solid body that consists mainly of carbonaceous material in a distinct shape.

      Notes

      Sometimes this term is also used for artificially (in the sense of technically) produced non‐shaped CARBON MATERIALS such as COKE, blacks, etc. This application of the term CARBON ARTIFACT is not recommended. Synonyms to the term CARBON ARTIFACT are “artificial carbon article” or “artificial


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