Aluminothermic reduction method for preparing aluminum-scandium alloy

Abstract

The invention provides an aluminothermic reduction method for preparing an aluminum-scandium alloy. The aluminothermic reduction method comprises the following preparation steps of (1) mixing scandium oxide powder, aluminum powder and cryolite Na3AlF6 powder, and continuously conducting ball milling in a plasma ball mill; and (2) directly adding ball-milled powder into high-temperature molten aluminum, preserving heat for 60 minutes, fully stirring, uniformly mixing, cooling and casting to obtain the aluminum-scandium intermediate alloy. The aluminum-scandium alloy prepared by the preparation method disclosed by the invention is high in yield and high in scandium content; and according to the aluminum-scandium alloy prepared through the method, the scandium content ranges from 2.0% to 4.0%, and the scandium yield is larger than 98%.

Description

technical field [0001] The invention relates to the technical field of aluminum alloys, in particular to an aluminothermic reduction method for preparing aluminum-scandium alloys. Background technique [0002] Scandium is a soft, silvery-white transition metal. The content of scandium in the earth's crust is about 0.0005%, which is a very rare metal material. Adding a small amount of scandium to aluminum alloy can form Al 3 Sc intermetallic compounds promote grain refinement and increase the recrystallization temperature by 250°C to 280°C. They are the most effective modifiers in aluminum alloys, greatly improving their mechanical properties, welding properties, formability and corrosion resistance. . Therefore, aluminum scandium alloys show great application prospects in the fields of automobile lightweight, aerospace, military weapons, ships and so on. In addition, in the fields of flat panel display and large-scale integrated circuits, the use of aluminum-scandium all...

AI Technical Summary

Problems solved by technology

[0007] In order to solve the above-mentioned deficiencies in the prior art, the present invention provides an aluminothermic reduction method for preparing aluminum-scandium alloy, which solves the problems of low scandium yield and low scandium content in the background art. Scandium and aluminum powder are used as raw materials, and the dielectric barrier discharge plasma-assisted ball milling method is adopted. Through the coupling of plasma and mechanical ball milling, it is very effective to accelerate the refinement of powder and promote the process of mechanical alloying, and significantly reduce the reduction reaction of aluminum / scandium oxide activation energy, promote the diffusion between solid-solid atoms, and greatly enhance the low-temperature synthesis ability of compounds