Sealed smelting casting method for magnesium-based intermediate alloy containing low-melting point metal element

Abstract

The invention discloses a sealed smelting casting method for a magnesium-based intermediate alloy containing a low-melting point metal element. Magnesium and a low-melting point element are prepared into an intermediate alloy with stable composition; the low-melting point element in the intermediate alloy is barely burnt, the composition is stable without segregation, and the intermediate alloy can be used for preparing an intermediate alloy in the smelting process of other magnesium alloys, thereby improving the yield of the low-melting point alloy element in the smelting casting process and realizing stable production. According to the method disclosed by the invention, the magnesium alloy containing the low-melting point element is smelted and cast after being sealed by a steel barrel, and six magnesium-based intermediate alloys of Mg-Hg, Mg-Ga, Mg-In, Mg-Sn, Mg-Bi and Mg-Pb containing different low-melting point alloy elements are successfully prepared; the process is simple, the composition of the prepared magnesium-based intermediate alloy containing a low-melting point metal element is uniform, the loss of the low-melting point element is little, and the method is successfully applied to actual production.

Description

technical field [0001] The invention relates to a method for smelting and casting a magnesium-based master alloy containing low-melting-point metal elements in a completely sealed manner to obtain a master alloy with less burning loss and uniform composition of low-melting-point metal components. Background technique [0002] With the development and use of new light metal materials, magnesium alloys have been widely used in many fields such as aerospace, rail transit, automobiles, 3C products, electronic devices, and chemical power sources because of their unique performance advantages such as low density and high strength. [0003] Among the various magnesium alloy systems, the main alloy systems currently used in industry are divided into three categories: Mg-Al-Zn series, Mg-Zn-Zr series and Mg-RE (rare earth) series. With the continuous expansion of the application field of magnesium alloys, the types of magnesium alloy alloys continue to increase. Some new alloy elemen...

AI Technical Summary

Problems solved by technology

However, during the melting and casting process of magnesium alloys, the temperature of the magnesium melt is between 700°C and 900°C, and the casting temperature of magnesium alloys is also between 700°C and 720°C, which will cause these added low melting point alloy elements to be smelted and cast at high temperatures. Oxidation and burning loss are particularly serious

For example, when elements such as mercury, gallium, or indium are added, when these elements are directly added to the magnesium melt, before these elements are alloyed with the magnesium melt at high temperature, these elements have been volatilized at high temperature or Oxidized, the elements with low melting point are particularly burned

In addition, during the magnesium smelting process, it is necessary to add solvents such as covering agents and refining agents to the magnesium melt to reduce the oxidation of the magnesium melt, especially to prevent the burning of the molten magnesium itself at high temperatures, and these solvents will also It is easy to form slagging with metal elements with low melting point, resulting in the loss of these low melting point elements, such as adding lead, tin, bismuth and other elements, because the density of these elements is far higher than that of magnesium, and the slagging reaction with the solvent is very easy. It is easy to form slag and precipitate to the bottom of the magnesium alloy melt to cause loss

Therefore, based on the above reasons, the conventional method of directly adding low-melting point elements to the magnesium melt is unsuccessful, the element loss is large, the yield is low and unstable, and mass production cannot be realized