PURPOSE: To perform the electric resistance welding of various stocks for can starting with a tin free steel by irradiating a laser beam on the surface of the overlapping part of the welding zone in advance prior to the welding.
CONSTITUTION: The welding is performed by irradiating a laser beam in advance on the whole part or one part of a steel sheet-steel sheet contact faces, 6, 7 and steel sheet-welding electrode contact faces 5, 8 in case of the electric resistance welding of the can stock like the tin-free steel coating with an extremely thin chrome plating on the steel sheet surface. By this laser irradiation, the chrome oxide layer 1 and metallic chrome layer 2 on the surface of the welding zone are completely removed with evaporation or alloyed with the surface material and yet the produced ultrafine powder is completely removed. The electric resistance welding for various can stocks including the tin free steel which was regarded as impossible in the past can therefore be performed easily.
KABASAWA MAKOTO
NAKADA KIYOKAZU
KOSUGE SHIGECHIKA
WATANABE ITARU
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