Manganese ingot

Electrolytic manganese sheet has a large surface area and a light specific gravity, which causes serious burning loss when used as an alloy additive. Therefore, electrolytic manganese sheet is generally re-dissolved and ingot cast to make it easy to add and small burning loss. It is mainly used for the production of special steel, nonferrous metal alloys, raw materials for the production of soft magnetic materials, welding electrode coating, diamond contact coal, etc.

The main functions of manganese ingot in steelmaking are deoxidation, desulfurization and alloying elements.

(1) Used as deoxidizer

In order to improve the quality of steel during steelmaking, it is necessary to remove carbon, sulfur and other harmful impurities from molten iron. The simpler process is oxidation. However, some iron and impurity elements are oxidized together to form ferrous oxide. The solubility of ferrous oxide in molten steel increases the oxygen content in molten steel. The increase of oxygen content will have adverse effects on the properties of steel. Therefore, steel has strict requirements for oxygen content, generally not more than 0.02%, or even more stringent. Therefore, excess oxygen should be removed during steelmaking. Manganese is a kind of active metal, and its chemical properties are more active than iron. When manganese is added to molten steel, manganese will react with ferrous oxide to form oxide slag insoluble in molten steel, which floats on the liquid surface of molten steel and reduces the oxygen content in steel.

Although the deoxidization capacity of manganese in molten steel is lower than that of other elements (such as calcium, aluminum and silicon), it is still popular with steel enterprises because of its easy production and relatively low price. Especially for boiling steel, ferromanganese alloy deoxidization is an ideal deoxidizer. Because manganese has weak deoxidization ability, it can adjust the oxygen content in steel without removing too much oxygen and boiling. At the same time, the presence of manganese can also enhance the deoxidization ability of silicon and aluminum, because the deoxidization product MnO and other oxides (such as Si02) can form low melting point compounds, which is conducive to the removal from molten steel.

(2) Used as desulfurizer

Sulfur is present in steel water in the form of iron sulfide. High sulfur content in steel is easy to cause thermal embrittlement and reduce the mechanical properties of steel. Therefore, sulfur content should be controlled during steelmaking. The binding force of manganese and sulfur is greater than that of iron and sulfur. After adding manganese alloy, manganese sulfide with high melting point is easy to be formed together with manganese in molten steel and converted into slag, thus reducing the sulfur content in steel and improving the malleability and rolling ability of steel.

(3) As alloying element

Manganese can strengthen ferrite and refine pearlite, improve the strength, hardenability, hardness and wear resistance of steel, so it can become an important alloy element of various steels. For example, if 0.8% - 1.7% manganese is added to low alloy steel, the strength of steel can be increased by 20% - 30% compared with ordinary carbon steel.