Welding can body, welding can, manufacturing method of welding can body, and manufacturing method of welding can

摘要

This welded can body is constituted of a steel plate material formed from a tin-free steel plate or a resin coated steel plate wherein a tin-free steel plate is coated with a resin, overlapping corresponding parts with each other, and forming a weld part by resistance welding of the overlapped parts. Laser processing parts formed on at least one of four surfaces made up of two surfaces constituting electrode contact surfaces on sides that contact an electrode (A) during resistance welding and two surfaces constituting joining surfaces on sides where the steel plate material is joined together, have laser irradiation parts, wherein laser irradiation is carried out before resistance welding to eliminate chrome plating and expose the steel plate, separately disposed on parts to be welded to become the weld parts, on the steel plate material.