Note: Oxidation of Graphite Anodes

Heating carbon graphite anodes to destructively oxidize the parts to process embedded contaminants 

Carbon graphite anodes

Ambrell 20 kW induction heating system, custom multi-turn helical coil, 4 cap 1.0 μF workhead 

anodes 2.5 x 2.5 x 4 in (63 x 63 x 102 mm) 

1900 °F (1000 °C)

154 kHz

An air purge system is used to provide fresh air (≅25 f³/hr) to the part during the heat cycle and to provide a swirling action for maximum contact with the surface of the anode. The anode is placed inside the induction-heating coil and heated to a temperature of 1000 °C. After 2.5 hours, the anode burns to about 0.375 in diameter piece. A pyrometer/controller is used to provide constant temperature as the anode reduces in size.