Method for preparing mixed intermediate alloy of magnesium and light rare earth with double-cathode method

Abstract

The invention provides a method for preparing a mixed intermediate alloy of magnesium and light rare earth with a double-cathode method, and belongs to the technical field of thermometallurgy. A graphite crucible is taken as an anode, magnesium lanthanum praseodymium cerium with low concentration is taken as a liquid cathode and forms double cathodes with a molybdenum rod; an electrolyte is added to the graphite crucible for electrolyzing, and the mixed intermediate alloy of magnesium and light rare earth is obtained; the electrolyte is formed by mixing magnesium chloride, lanthanum praseodymium cerium chloride and potassium chloride; and lanthanum praseodymium cerium chloride and magnesium chloride are added in an electrolyzing process. According to the method, a large number of low-price surplus mixed light rare earth materials are taken as raw materials, metal magnesium and rare earth metal are not used, chlorides of mixed light rare earth and magnesium are used, rare earth ions and magnesium ions are electrolyzed and deposited under the action of double electrodes, so that the intermediate alloy with a melting point close to magnesium-mixed light rare earth eutectic temperature is generated. The method is low in cost and high in operability. The prepared mixed intermediate alloy of magnesium and light rare earth is a basic material for preparing a high-strength and corrosion-resistant magnesium alloy.

Description

technical field [0001] The invention belongs to a preparation method of a magnesium-mixed light rare earth master alloy and belongs to the technical field of pyrometallurgy. Background technique [0002] The invention belongs to a preparation method of a magnesium-rare earth intermediate alloy applied to new magnesium alloy materials. Magnesium-rare earth master alloys are the basic raw materials for the preparation of advanced new corrosion-resistant magnesium alloys for high-temperature applications. There are mainly three methods for preparing magnesium-rare earth master alloys, one is the pairing method, and the other is the magnesia thermal reduction method. These two methods have their own problems: the pairing method is difficult to avoid alloy composition segregation, because magnesium and most rare earth metals are in the There is a huge difference in specific gravity and melting point, and rare earths cannot be well dispersed in magnesium; the intermittent product...

AI Technical Summary

Problems solved by technology

There are mainly three methods for preparing magnesium-rare earth master alloys, one is the pairing method, and the other is the magnesia thermal reduction method. These two methods have their own problems: the pairing method is difficult to avoid alloy composition segregation, because magnesium and most rare earth metals are in the There is a huge difference in specific gravity and melting point, and rare earths cannot be well dispersed into magnesium; the intermittent production cost of magnesium thermal reduction method is high; the third is molten salt electrolysis, which includes liquid cathode method and co-precipitation electrolysis method.

[0010] The raw material used in the liquid cathode method is anhydrous rare earth chloride, and the co-precipitation electrolysis method uses anhydrous magnesium chloride. The dehydration process is complicated, especially the process of removing the last two crystal waters from magnesium chloride is extremely complicated and brings a lot of energy consumption. Material consumption and corrosion equipment issues that generate HCl