WELDING ELECTRODE, WELDING APPARATUS AND WELDING METHOD

摘要

According to an embodiment of the present invention, a welding electrode comprises: a body part for applying a current for spot welding while preventing a crack from generating in a high strength steel welded material of 780 MPa or more of tensile strength; and a contact end part formed in the body part to press the welded material. The contact end part can be provided in the tapered shape to form 5-30 degrees of the deformation angle between a deformation part of the welded material deformed by pressure of the contact end part, and an outer lateral part around the deformation part. According to the other embodiment of the present invention, a welding apparatus comprises: a device body; a welding electrode provided for the device body for spot welding a high strength steel welded material of 780 MPa or more of tensile strength by applying a current; and a sub pressure unit provided for the device body to be adjacent to the welding electrode, and vertically moving. The sub pressure unit is capable of applying pressure to the welded material to form 5-30 degrees of the deformation angle between a deformation part of the welded material deformed by pressure, and an outer lateral part around the deformation part.