MODIFIED-GRAPHITE TECHNOLOGY. Quarterly Report No. 1

Technical Report · Wed Jan 20 04:00:00 EST 1960

OSTI ID:4169535

Bradstreet, S W

The past year of study of fine, molded, multicrystalline graphites with particular reference to the interrelation among certain properties with the composition, fabricating techniques, and thermal treatments found to influence them are summarized. Within the limitations of the compositions and specimen size studied, conclusions have been drawn regarding the relation of these properties (density, volume electrical resistance, flexural modulus, thermal expansion coefficient, and flexural and tensile strength) to the rheology, gas permeability, and structure of the molded body. The best corformity of all specimens to a given mean is obtained when a thermoplastic binder-deficient mix is vacuum molded at an elevated temperature, carbonized slowly in an inert gas purge, and graphitized together. The internal error of a 30-specimen block is then found to be approximately four percent plus the error of the property measurement. Binder-rich mixes are more sensitive to treatment variations, but the desirable rheology of a binder-rich mix can be simulated without this variability by substituting moderate proportions of a thermal carbon for some of the coke flour. The theoretical promise of furfuryl alcohol as a binder has been experimentally confirmed. Unusual care is required in low-permeability mixes, to prevent rupture during baking. To an as yet undefined extent, this may be avoided by modifying the thermosetting FA binder with the thermoplastic coal tar pitch. (auth)

• Research Organization: Illinois Inst. of Tech., Chicago. Armour Research Foundation
• NSA Number: NSA-14-012924
• OSTI ID: 4169535
• Report Number(s): ARF-6038-8; LAR-20
• Country of Publication: United States
• Language: English

Related Subjects

ALCOHOLS
CARBIDES
CASTING
CEMENTS
COAL
CREEP
CRYSTALS
DENSITY
ELASTICITY
ELECTRIC CONDUCTIVITY
EXPANSION
FABRICATION
FAILURES
GASES
GRAPHITE
HEAT TREATMENTS
HIGH TEMPERATURE
INERT GASES
LATTICES
MEASURED VALUES
METALS, CERAMICS, AND MATERIALS
MIXING
POROSITY
TENSILE PROPERTIES
VACUUM
VARIATIONS
VOLUME