| 摘要 |
Molten metal is fed into a liquid-cooled horizontal caster through a ceramic nozzle to form a continuous wire or rod, that is drawn out of the exit end of the mold in incremental steps by a pair of intermittently-driven pinch rolls. The nozzle is preferably made of zirconium oxide, which is slightly porous and at temperatures above 1100 DEG F. has the property of allowing gas to pass through at a much greater rate than at lower temperatures. The nozzle is mechanically attached to the end of the liquid-cooled caster. A shroud, or manifold, surrounds the nozzle for at least a portion of its length, and also enclosed the interface between nozzle and caster. The manifold is supplied with a dry, inert gas such as argon, so that at elevated temperatures, any oxygen is purged from the pores of the zirconium oxide nozzle and is replaced by the inert gas, thereby eliminating any oxygen that would otherwise be present at the interface between the nozzle and the molten metal. Thus, there is formed at the interface surrounding the molten metal a shielding environment of inert gas which is totally non-reactive with the hot metal.
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