Arc Furnace - Arcro

This refers to a furnace in which two graphite rods are placed inside, and a high voltage is applied to them to create an arc, which serves as the heat source. The arc furnace that is widely used industrially is the consumable electrode vacuum arc furnace. This type of furnace is often used to manufacture high-grade steel, high-purity titanium, and zirconium. The metal to be melted and smelted with the arc is held on top as the negative electrode, and a water-cooled copper mold is used as the positive electrode in a vacuum or inert gas atmosphere. A low-voltage, high-current arc is applied to melt the metal, and the electrode rod is lowered as the molten metal accumulates in the mold. The metal directly below the arc is molten, forming a so-called metal pool, which gradually solidifies from the bottom up. If melting is performed in a vacuum, it drips from the tip of the electrode, and while the metal pool is forming, degassing and other processes progress, and the refining reaction takes place. To obtain a stable arc, it is common to install an automatic device for lowering the upper electrode and a device for creating a magnetic field using a DC solenoid around the mold. A skull furnace, which is designed to be able to pour molten metal into a mold of an appropriate shape, is also a type of arc furnace. Electric furnaces used in steelmaking are also called arc furnaces. [See alternative terms] Vacuum metallurgy

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

炉内に黒鉛棒を2本入れ，これに高電圧をかけアークを飛ばして熱源とする炉をいうが，工業的に広く用いられているアーク炉は，消耗電極型真空アーク炉である．このような炉は，高級な鋼や高純度チタンやジルコニウムの製造によく用いられている．アークで融解製錬しようとする金属を上に保持してマイナスの電極とし，真空中あるいは不活性ガス雰囲気中で水冷銅鋳型をプラス極として，低電圧，高電流のアークを飛ばして融解し，鋳型中に湯がたまるに従い電極棒を降下させていく．アークの直下の金属は溶融していて，いわゆるメタルプールをつくり下のほうから徐々に凝固していく．真空中で融解を行えば電極先端から滴下し，メタルプールをつくっている間に脱ガスなどが進行し，精錬反応が行われる．安定なアークを得るために，上部電極の下降の自動装置や鋳型のまわりの直流ソレノイドによって磁場をつくる装置を設置するのが普通である．融湯を適当な形状の鋳型に鋳込むことができるように工夫されたスカル炉(skul furnace)もこのアーク炉の一種である．また，製鋼用電気炉もアーク炉とよばれている．[別用語参照]真空冶金

出典　森北出版「化学辞典（第2版）」化学辞典 第2版について　情報