Special features of resistance welding aluminium alloys using nanostructured aluminium-nickel and aluminium-copper foils

摘要

The application of nanostructured foils in the resistance butt welding of aluminium alloys results in the highly concentrated generation of heat in the joint reducing the welding time and preventing softening of the metal. When using a foil of the Al-Ni system in resistance butt welding of aluminium alloys, an additional amount of heat is generated in the joint as a result of the exothermic reaction between aluminium and nickel. The development of the exothermic reaction depends on the heating rate in welding. The optimum heating rate for producing high-quality welded joints is 500-800 deg C/s. The application of copper-aluminium nanostructured foils greatly reduces the welding temperature of aluminium alloys (by 100-150 deg C) as a result of formation of the Al-Al,Cu eutectic. This is of particular importance in welding thermally unstable aluminium alloys.