Preparation method of aluminum-scandium intermediate alloy, aluminum-scandium intermediate alloy and aluminum-scandium alloy

Abstract

The invention provides a preparation method of an aluminum-scandium intermediate alloy, an aluminum-scandium intermediate alloy and an aluminum-scandium alloy. The preparation method comprises that a scandium-containing compound and an aluminum-containing raw material are added into a first reactor and undergo a thermal reduction reaction to produce a liquid aluminum-scandium intermediate alloy, wherein the aluminum-containing raw material contains aluminum and/or an aluminum alloy, the liquid aluminum-scandium intermediate alloy is added into a second reactor with melt salt and is subjected to slag extraction treatment, wherein the density of the melt salt is less than density of the liquid aluminum-scandium intermediate alloy, and the liquid aluminum-scandium intermediate alloy subjected to slag extraction treatment is cooled and cured so that an aluminum-scandium intermediate alloy cast ingot is obtained. The preparation method realizes a thermal reduction reaction and a slag extraction treatment process in different reactors, realizes semi-continuous production of the aluminum-scandium intermediate alloy, improves aluminum-scandium intermediate alloy production efficiency and improves aluminum-scandium intermediate alloy uniformity.

Description

technical field [0001] The invention relates to the technical field of aluminum alloys, in particular to a method for preparing an aluminum-scandium master alloy, an aluminum-scandium master alloy and an aluminum-scandium alloy. Background technique [0002] Scandium is the element that has the strongest grain refinement and recrystallization inhibitory effect on aluminum alloys found so far. Adding a small amount of scandium to aluminum alloy can greatly improve the strength, corrosion resistance, welding performance and other properties of aluminum alloy. The melting point of scandium is 1541°C, while the melting point of aluminum is 660.37°C. There is a big difference in the melting points of these two metals. If scandium is directly added to the aluminum alloy, it not only requires a higher temperature, which consumes too much energy, but also easily causes the segregation and aggregation of scandium in the aluminum alloy. Therefore, in the production process of scandi...

AI Technical Summary

Problems solved by technology

[0007] However, the above-mentioned preparation methods all have the following disadvantages: (1) the amount of slag in the compound salt composed of scandium oxide and solvent is large, the quality of the compound salt is about 20-200% of the alloy mass, and the concentration of scandium oxide in the molten salt is very low, Generally be less than 15%, cause reaction speed to be slow, prolong reaction time; (2) partial scandium oxide is dissolved in compound salt and can not react completely, has reduced the yield of scandium, and the yield of scandium in the prior art is 60-85% , the yield of scandium in individual examples can reach 89%; (3) the aluminum oxide in the aluminum-scandium intermediate alloy liquid is transferred to the solvent only by diffusion and mass transfer, and the mass transfer rate is slow, which not only prolongs the production cycle, but also may cause intermediate The inclusion of alumina in the alloy product reduces the purity of the intermediate alloy; (4) The whole process basically includes the stages of charging - heating - reaction - heat preservation - pouring, etc., and after casting, it is necessary to wait for the reaction furnace to cool and take out the ingot before proceeding to the next step. Furnace production, not continuous production

The above shortcomings will lead to long production cycle and low production efficiency of Al-Sc master alloy