Microstructures and Properties of Friction Welded Joint of Dissimilar Materials under External Electric Field

摘要

Formability of materials is very important for the friction welding of dissimilar materials. The resistance to formability of metals can be reduced by the electric induced plasticity under an externally applied electric field. Friction welding of T2 Copper and 1Cr18Ni9Ti stainless steel was carried out under electric field with an attempt to improve the friction weldability of these two materials. The influence of different types of external electric field on the microstructure of the welded joints was examined and distributions of alloying elements in the weld metal area were analyzed using EDX. The torsion strength of joints produced using different welding parameters was tested. It was indicated that the dynamic recrystallization of the weld metal was enhanced by the applied electric field. The use of an electric field has resulted in more homogenous distributions of the recrystallized grains in the weld zone when the specimen was connected to the cathode of the power supply. The diffusion distance of the main alloying elements in the material increased under AC electric field or electrostatic field with the specimen connected to the cathode of the power supply. The torsion strength of the welding joints was improved under external an electric field, especially an AC electric field.