Graphite crystallites

Graphite is commonly produced by CVD and is often referred to as pyrolytic graphite. It is an aggregate of graphite crystallites, which have dimensions (L ) that may reach several hundred nm. It has a turbostratic structure, usually with many warped basal planes, lattice defects, and crystallite imperfections. Within the aggregate, the crystallites have various degrees of orientation. When they are essentially parallel to each other, the nature and the properties of the deposit closely match that of the ideal graphite crystal. 

The carbon layers of carbon black rearrange to a graphitic order, beginning at the particle surface at temperatures above 1200 °C. At 3000 °C, graphite crystallites are formed and the carbon black particles assume polyhedral shape. 

Mr. McCartney. From a study of electron micrographs, we estimate that a very large proportion of the apparent vitrain band in this meta-anthracite consists of graphite crystallites or platelets. The intensity and sharpness of graphite peaks in diffraction patterns supports this view. 

This ideal carbon should also be as pure as is practical, and have the required electrical conductivity and mechanical strength to function as plant anode material. Anode carbon consists of three elements (1) graphite crystallites in various sizes, shapes, and... 

When pitch binder is pyrolyzed during the carbon bake operation, it is converted from an isotropic liquid, with no structural order, to a liquid-crystal (called mesophase) having a layered structure which is finally converted to layers of carbon atoms in a hexagonal lattice of graphite crystallites. These crystallites of binder coke become more disordered and crosslinked into a more-isotropic coke as the pitch QI content increases. Such moderately-isotropic coke, in contrast to highly-anisotropic microstructure (10), is preferred binder coke because it forms both physical and chemical bonds between filler coke particles which are stronger and more oxidation-resistant (8,9). 

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