A Study on the Hot Pressure Welding Joints of Aluminium and Copper after the Exposure at Elevated Temperature

Abstract

Hot pressure welding joints of aluminium and copper are studied to find the application as a transition piece for use in aluminium conductors of the electric power distribution facilities. In paticular, the effect of a long term exposure at elevated temperature on the weld joint is discussed and the change of mechanical and metallurgical properties due to the exposure is experimentally investigated.
In conculsion, the good welded joints with little intermetallics can be easily obtained by this welding procedure, but three kinds of intermetallics (θ, η2, γ2) are observed at the weld interface after some exposure at elevated temperature, and the reduction of the strength at the weld is found as the growth of intermetallics reaches to about 1, u in width.
Equivalent diffusion coefficient of the joint of aluminium and copper is calculated from micrographic determination of the width of intermetallics and applied to determine the estimated life at a working temperature as the electric conductor.