Welding method

A welding method comprising welding an upper plate and a lower plate overlapped with the upper plate by irradiating a surface of the upper plate with a laser beam,

• the welding comprising:
• forming an auxiliary welding path that is continuous and comprises a reciprocating or circling path;
• and
• forming a main welding path that intersects a welding advancing direction and that comprises turning points, after formation of the auxiliary welding path,
• wherein molten metal is supplied from the auxiliary welding path to the main welding path, and
• wherein the main welding path has a shape of triangular waveforms that are continuously connected, and comprises:
• an initial region continuous from the auxiliary welding path;
• and
• a subsequent region that is welded continuously from the initial region,
• wherein the subsequent region includes an end point of welding, and has a larger turnaround pitch than the initial region,
• wherein, in the forming of the main welding path, the upper plate and the lower plate are arranged in an inclined manner with respect to a horizonal plane when viewed parallel to the welding advancing direction, and
• wherein, in the forming of the main welding path, an amount of energy applied by the laser beam in an area passing through a first turning point among the turning points is designed to be larger than an amount of energy applied by the laser beam in an area passing through a second turning point lower than the first turning point among the turning points.