The degassing device is installed between the furnace and the filter box, and the quantitative refining gas is brought into the metal by the rapid rotating graphite rotor; by relatively high-speed cutting through graphite rotor and aluminum, the gas comes into fine bubbles and evenly distribute in the aluminum; because the hydrogen partial pressure in the bubble is zero, and the hydrogen partial pressure in the aluminum is high, so the hydrogen in the aluminum gradually diffuses into the bubble; at the same time, the metal and non-metallic inclusions in the aluminum are adsorbed on the surface of the bubbles, and then the bubbles and inclusions float up to the surface; thus achieving the purpose of removing hydrogen and inclusions in the aluminum.
Requirements of refractory for degassing box:
Good volume stability
Good thermal shock resistance
Not easy to crack
Excellent resistance to aluminum penetration