Graphite having improved thermal stress resistance and method of preparation

Patent · Tue Feb 26 04:00:00 EST 1980

OSTI ID:7247638

Kennedy, C R

An improved method for fabricating a graphite article comprises the steps of impregnating a coke article by first heating the coke article in contact with a thermoplastic pitch at a temperature within the range of 250--300 C at a pressure within the range of 200--2,000 psig for at least 4--10 hours and then heating said article at a temperature within the range of 450--485 C at a pressure of 200--2,000 psig for about 16--24 hours to provide an impregnated article; heating the impregnated article for sufficient time to carbonize the impregnant to provide a second coke article, and graphitizing the second coke article. A graphite having improved thermal stress resistance results when the coke to be impregnated contains 1--3 wt.% sulfur and no added puffing inhibitors. An additional improvement in thermal stress resistance is achieved when the second coke article is heated above about 1,400 C at a rate of at least 10 C/minute to a temperature above the puffing temperature. 6 figs.

• Assignee: Dept. of Energy, Washington, DC (United States)
• Patent Number(s): US 4190637; A
• Application Number: PPN: US 5-925721
• OSTI ID: 7247638
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation & Manufacture
360603 -- Materials-- Properties
CARBON
ELEMENTAL MINERALS
ELEMENTS
FABRICATION
GRAPHITE
IMPREGNATION
MINERALS
NONMETALS
STRESSES
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 0400-1000 K
THERMAL STRESSES