Preparation method of aluminum-scandium master alloy

Abstract

The invention relates to a preparation method of aluminum-scandium master alloy, which belongs to the technical field of high-performance aluminium alloy raw material preparation. The preparation method is characterized in that: the method adopts the following raw materials: Sc2O3, pure aluminium and a molten salt system, and comprises the following steps: mixing pure aluminium, Sc2O3 and the molten salt system uniformly once and adding the materials in a crucible; putting the crucible in a resistance furnace for heating and smelting, raising the temperature to 950+ / -20 DEG C, and keeping the temperature for 90 to 120 minutes; and casting and sampling after heat preservation. The molten salt system comprises NF4HF, NaF, KCl, NaCl, nNaF AlF3 (sodium cryolite) and nKF AlF3 (kalium cryolite) in a mixing ratio of 10:8:5.4:5.4:3:3; and the molten salt system, pure aluminium and Sc2O3 are added in the crucible in a mass ratio of 30+ / -1.5:100:4+ / -0.1. Compared with the prior art, the method has the advantages that: the prepared aluminum-scandium master alloy has smaller grain size, even distribution of Al3Sc, no obvious agglomeration and small size. When used in subsequent preparation of Sc-containing alloy, the master alloy has excellent refining effects.

Description

technical field

[0001] The invention relates to a method for preparing and improving an aluminum-scandium master alloy. It belongs to the technical field of high-performance aluminum alloy raw material preparation. Background technique

[0002] Scandium (Sc) is an element found so far that has the strongest grain refining effect on aluminum alloys and inhibits recrystallization. Adding scandium to aluminum alloy can greatly improve the properties of the alloy, which has become a research hotspot at home and abroad. The melting point of scandium is 1541 ℃, and the melting point of aluminum is 660 ℃. The melting point of the two metals is very different. Adding scandium to aluminum must be in the form of a master alloy. Therefore, the preparation of aluminum-scandium master alloy is a key link in the production of high-performance aluminum-scandium alloys. .

[0003] At present, the preparation methods of scandium-containing master alloys at home and abroad mainly include c...