Method for producing aluminium-lithium alloy with high lithium content by low-temperature molten salt electrolysis

Abstract

The invention provides a method for producing an aluminium-lithium alloy with high lithium content by low-temperature molten salt electrolysis. In an electrolytic furnace, aluminium is taken as a cathode, a cathode sleeve is sheathed thereon, graphite is taken as an anode, an electrolyte system is formed from LiCl and KCl, wherein, the weight ratio of LiCl: KCl is equal to 45: 55, the electrolysistemperature is 380-450 DEG C, the self-consumption cathode method is adopted for carrying out electrolysis, the current density of the cathode is 1-3.0A / cm<2>, the current density of the anode is 0.5A / cm<2>, the cell voltage is 4.1-5.6V, LiCl is supplemented during the electrolysis process for leading the mixing ratio of LiCl: KCl of the electrolyte to be in the vicinity of an eutectic point, theliquid aluminium-lithium alloy with high lithium content is deposited in the vicinity of the cathode in a molten salt electrolytic cell by 1-4 hours of electrolysis, and the solid aluminium-lithium alloy is prepared by solidification. The method can obtain the liquid aluminium-lithium alloy with evenly distributed alloy components at low temperature. The method can avoid the defects of burning loss of lithium during the doping process and the like, simultaneously save energy consumption of doping, mixing and melting process, avoid cracking of the cathode and uneven components, and avoid the defects of burning loss of the lithium caused by higher temperature and volatilization loss of LiCl.

Description

(1) Technical field [0001] The invention relates to a method for producing an aluminum-lithium master alloy by molten salt electrolysis, and belongs to the field of electrometallurgy. (2) Technical background [0002] Al-Li alloy is a lightweight alloy with good comprehensive performance and great development potential. It can reduce the weight of the component and increase the rigidity by replacing the ordinary Al alloy. Therefore, it is considered to be an ideal structural material for aerospace vehicles in the 21st century. It also has great application potential in ships and weapons industry. The material preparation and parts manufacturing process of Al-Li alloy are not different from ordinary aluminum alloys in principle, and the technology and equipment of ordinary aluminum alloys can be used; Al-Li alloys are used to replace traditional aluminum alloys used in aircraft, no need for adaptation In addition, the forming and maintenance of Al-Li alloys are more convenie...

AI Technical Summary

Problems solved by technology

However, if such a high electrolysis temperature is used, the volatilization loss of lithium chloride is relatively serious, which will increase the cost of raw materials and cause environmental pollution, so it is not suitable for industrial production.