Abstract: A method for reducing impurities in magnesium comprises: combining a zirconium-containing material with a molten low-impurity magnesium including no more than 1.0 weight percent of total impurities in a vessel to provide a mixture; holding the mixture in a molten state for a period of time sufficient to allow at least a portion of the zirconium-containing material to react with at least a portion of the impurities and form intermetallic compounds; and separating at least a portion of the molten magnesium in the mixture from at least a portion of the intermetallic compounds to provide a purified magnesium including greater than 1000 ppm zirconium. A purified magnesium including at least 1000 ppm zirconium and methods for producing zirconium metal using magnesium reductant also are disclosed.
Abstract: Provided are a magnesium-based alloy and a manufacturing method thereof. In the method, a magnesium alloy is melted into liquid phase, and an alkaline earth metal oxide is added into a molten magnesium alloy. The alkaline earth metal oxide is exhausted through surface reduction reaction between the melt and the alkaline earth metal oxide. Alkaline earth metal produced by the exhaustion reacts with Mg and/or other alloying elements in the magnesium alloy so that an intermetallic compound is formed. The magnesium prepared by the method is excellent in fluidity and hot-tearing resistance. To this end, the alkaline earth metal oxide added is CaO, and the added amount of CaO is 1.4 to 1.7 times the target weight of Ca to be contained in the final Mg alloy.
Type:
Application
Filed:
March 24, 2011
Publication date:
September 29, 2011
Applicant:
KOREA INSTITUTE OF INDUSTRIAL TECHNOLOGY
Abstract: The magnesium melting furnace (1) has a plurality of chambers. The material to be melted is fed into a melting chamber (2) through a charging chute (20), one end of which terminates under the surface of the melting bath. The melt is slowly transferred into a holding chamber (4) through a passage (3) situated in the lower third of a dividing wall (11) above a layer of impurities settling at the bottom (14) of the melting chamber (2). The melt slowly flows through the holding chamber (4), with impurities rising to the surface or settling on the bottom (15). The purified melt flows through a second passage (5) situated in the lower third of a second dividing wall (12) into a metering chamber (6). The melt can be removed from the metering chamber (6) through a transfer pipe (28) using a metering pump (27). The magnesium melting furnace (1) makes it possible to simultaneously melt, purify and remove the magnesium in metered quantities.
Abstract: The invention relates to a process for refining crude magnesium, and, in particular, the magnesium obtained by reducing the magnesium ore using iron-silicon.The process consists in treating the liquid magnesium with a metallic sulphide such as iron monosulphide, iron bisulphide or molybdenum bisulphide.The sulphides are contacted with the metallic bath which is agitated to promote the liquid-solid reactions and the formation of insoluble products which precipitate.This contacting is followed by decantation of the insoluble products and their separation from the refined magnesium.The process permits a significant reduction in the contents of calcium and silicon.
Abstract: Hydrogen is essentially removed from molten magnesium by the use of a degassing step, thereby substantially avoiding the formation of zirconium hydride when zirconium and silicon are added to the molten magnesium, after the degassing, in order to precipitate iron contamination in the magnesium as an intermetallic compound comprising Fe, Zr, and Si; the ratio of the three metals in the intermetallic compound can vary over a wide range. By essentially avoiding the formation of slow-settling insoluble ZrH.sub.2, the iron removal is more efficient and the settling of the insolubles is expedited. Also, the Fe and Si are more effectively and consistently precipitated.