Welding equipment for metallic materials and method for welding metallic materials

Abstract

A welding equipment for metallic materials capable of performing heat treatment such as tempering based on partial heating in spot welding is provided. The welding equipmentsandwiches metallic materialswith a pair of electrodes, and heats different regions of the metallic materialsby energization, with the pair of electrodesmaintained at the same position with respect to the metallic materials. The welding equipment includes a first heating meansconnected to the pair of electrodesfor heating and welding the internal region of the circle defined by projecting the cross-sectional area of the axis of the electrodes on the metallic materials by applying power having a low first frequency, a second heating meansfor heating a ring-shaped region along the circle by applying power having a second frequency that is higher than the first frequency, and an energization control unitfor independently controlling the first and the second heating means