Graphite heating elements

Among those heating elements which require the use of neutral, reducing atmospheres, or vacuum. Mo- wire or W-wire in the form of heating coils, graphite in the form of rods or semi-cylinders, are most often used. Iridium wire is also used but it is very expensive. Both Mo and W wire cire usable up to 2800 °C while Ir can be used only to 2400 °C. Graphite heating elements can be used above 3000 °C. 

Samples analyzed in the dilatometer up to temperatures above ISOO C lost considerable amounts of silicon through evaporation that was deposited on the graphite sample holder in the dilatometer. These samples consisted mostly of TiC. Since carbon was present in the furnaces through the graphite heating elements and sample holder/crucible, the decomposition of Ti3SiC2 is likely to follow the reaction initially proposed by Racault et al. ... 

Rod, wire, and ribbon resistance heaters are also used. Silica carbide, quartz, and graphite heating elements are also available. 

The reaction furnace is heated by direct passage of a current through graphite heating elements. The reaction crucibles are made of graphite, have a cylindrical shape, with a slightly conical base, and are put into the furnace without a cover. The crucibles can be very simply changed after each analysis. A new crucible is used for each determination. 

Insulating substrate in ribbon heaters in combination with a pyrolytic graphite resistance heating element. 

E. S. Domalski, G. T. Armstrong. The Heats of Combustion of Polytetrafluoroethy-lene (Teflon) and Graphite in Elemental Fluorine. J. Res. Natl. Bur. Stand. 1967, 71A, 105-118. 

Metallurgical Applications, Structural Graphite Shapes, Electrical Heating Elements, Carbon and Graphite Powder and Particles)... 

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