Ferroalloys

Also called ferroalloys. In the broad sense, they are alloys necessary for steel manufacturing. Ferroalloys are broadly divided into those used for deoxidation of steel, and those used as additives to adjust the composition of alloy steel or cast iron. A representative example of the former is ferrosilicon, an Fe-Si alloy with 50-100% Si by mass, and an example of the latter is ferronickel, with a general composition of Ni + 20% Co by mass, 2.7% C by mass, 5.0% Si by mass, and 1.2% Cr by mass. They are mainly produced by carbon reduction in an electric furnace from ores containing the oxides of each component. Other methods include thermite reaction and electrolytic reduction, as with metallic manganese and chromium metal.

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

合金鉄ともいう．広義には鉄鋼製造に必要な合金類．フェロアロイは鋼の脱酸を目的とする脱酸用と，合金鋼あるいは鋳鉄の成分調整を目的とする添加用とに大別される．前者の代表例はフェロシリコンで50～100質量％ SiのFe-Si合金，後者の例はフェロニッケルで，一般的な組成はNi＋20質量％ Co，2.7質量％ C，5.0質量％ Si，1.2質量％ Crである．製造方法は，おもに各成分酸化物を含む鉱石から電気炉を用いた炭素還元によってつくる．そのほかにはテルミット反応を利用した方法，金属マンガンや金属クロムのように電解還元による方法などがある．

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