ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Structure within calcined and graphitized cokes from a delayed coker is investigated by optical microscopy, etching with chromic acid solution and scanning electron microscopy. The grains of mosaics of a coal extract delayed coke are clearly identifiable. Etching studies of needle-cokes are informative giving the detail of pore wall structure, of the sub-divisions of structure within the macro-needles (1 mm diameter) of needle-coke, i.e. the acicular flow domains, of disclinations within domains and of a layered “sedimentary” structure within domains. The etching characteristics of graphitized needlecokes are quite distinct from those of calcined needle-cokes. In the former, basal planes of acicular flow domains etch into small bundles, 1 to 2 μm in length, with development of fissures every 1 μm apart and some 0.1 μm across. Features observed in the topography of etching may assist in the understanding of how needle-cokes accommodate thermal and mechanical stresses.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00549818
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