| 摘要 |
PROBLEM TO BE SOLVED: To obtain a weld zene of a sound and high quality without blow hole at low cost by using a laser beam of a specific wavelength and a nitrogen containing shield gas of a specific composition and welding a carbon steel. SOLUTION: A carbon steel of a general steel is welded by using a laser beam. In this time as the laser beam, the laser beam of CO gas laser or YAG laser, etc., having the wave-length being <=8.2μm is used. Further, as the shield gas, an inert gas of containing >=5 volume% of an inexpensive nitrogen. Therefore, the generating amount of plasma is reduced and the weld zone having deep penetration and a small amount of solution of nitrogen is obtained. |
