| 摘要 |
PURPOSE:To increase efficiency of utilization of laser beam energy and perform more uniform welding of high quality in carrying out welding supplying plasma forming gas to the vicinity of weld zone and supplying added metal continuously, by accelerating separation of droplets at the tip of added metal. CONSTITUTION:The focal point of a laser beam irradiator 1 is placed near the surface of a material 2 to be welded, and specified quantity of He gas is supplied toward the point of incidence of laser beam to the base metal through a gas flow passage and a heat resisting pipe 11. Plasma atmosphere is formed near the weld zone, and the beam 3 is incident upon the weld zone through the atmosphere. An added metal wire 6 is fed through a guide 8 and a pipe 11. The tip of the wire is molten by the heat of plasma atmosphere before it arrives at the beam, and moves to the upper part of butted end faces of welding and forms a bridge. This is heated and kept hot by plasma atmosphere and mixes with molten metal of welded end faces. At this time, molten metal at the tip of the wire is moved, while it is in a state of small droplet, by gas flow from the tip of the pipe 11 to just in front of the point of incidence of the beam resisting reaction force of evaporation of laser welding. |
