Abstract: This invention provides a new through weld method to carry out welding of a base metal made of aluminum or that of aluminum alloy using high energy beams wherein a shield gas ambience (an inert gas ambience) to cover a welding site in a submerged-scar is formed, even a shield gas ambience (an inert gas ambience) to cover a welding site irradiated by the high energy beams. Since the former shield gas ambience to cover the submerged-scar pushes the keyhole against the gravity and/or the gas pressure force of the latter shield gas supplied to the laser irradiation side, then the forming of hang down of beads and the resultant projection of the welding base metal are prevented.

Abstract: A twin spots pulse laser welding apparatus is disclosed which is used for providing a defect-free weld in a butt welding gap. The welding apparatus comprises a YAG laser oscillator 6, a chopper circuit for controlling the value of the lamp current of the oscillator, a chopping controller 12, a control panel 10 and a pulse generator 11 for applying a lamp current base value Wb and a peak value Wp and a pulsating pulse to the controller, and a twin spots laser head 14 for converging a laser beam delivered from the YAG laser oscillator to two foci 20R, 20L which are distributed in x direction with a very small spacing therebetween. YAG laser beam delivered from the YAG laser oscillator 6 is guided through an optical fiber cable 9 to the laser head.

Abstract: A laser light L is emitted from a laser light source 6 to works 1, 2, to form a laser molten weld pool 3, and immediately thereafter, an arc molten weld pool 4 is formed using an arc welding machine 7; thereby plates 1, 2 are welded. The arc welding machine 7 is provided with a filler wire to form a bead 5 on the plate 1. With the welding process according to the present invention, works can be efficiently and securely welded regardless of shape and material of the works.

Abstract: A combined YAG laser/arc welding apparatus is disclosed which performs a welding operation with a large depth of fusion and a deep fusion at a high efficiency. The welding apparatus includes an arc electrode which targets a point on a welded member where a laser beam from a YAG laser is focused. While an arc power supply is connected between the arc electrode and the welded member, the welded member is irradiated by the YAG laser to produce plasmoid gasses and metal vapors or a plume which is effective to start an arc from the arc electrode. A combined YAG laser/arc welding operation takes place while keeping the plume within and without a keyhole. Welded surface is covered by a hood, and a shielded gas passed through a commutation metal network surrounds the welded focus to prevent an oxidation and keeps the plume maintained. A filler wire is fed to a molten pool.

Abstract: A twin spots pulse laser welding apparatus is disclosed which is used for providing a defect-free weld in a butt welding gap. The welding apparatus comprises a YAG laser oscillator 6, a chopper circuit for controlling the value of the lamp current of the oscillator, a chopping controller 12, a control panel 10 and a pulse generator 11 for applying a lamp current base value Wb and a peak value Wp and a pulsating pulse to the controller, and a twin spots laser head 14 for converging a laser beam delivered from the YAG laser oscillator to two foci 20R, 20L which are distributed in x direction with a very small spacing therebetween. YAG laser beam delivered from the YAG laser oscillator 6 is guided through an optical fiber cable 9 to the laser head.

Abstract: A circular blank made of a steel plate is lapped onto an Al-based plate in lapped areas of the Al alloy plate and another steel plate. Then, the three members are pressed by a pair of electrodes, and a welding current is allowed to flow between both the electrodes, thereby sequentially performing the melting of a current-supplied portion of the Al alloy plate and a portion near the current-supplied portion, the elimination of a molten portion by a partial bulgy deformation of the blank toward the Al alloy plate, the abutment of the bulgy deformed portion against the steel plate, and the resistance-welding between the bulgy deformed portion and the steel plate.

Abstract: A powder material for use in resistance welding articles of aluminum comprises a mixture of 10-50% by weight of a liquid resin and the remaining proportion of a magnesium powder or a blend of magnesium and aluminum powders. Also a method of resistance welding articles of aluminum comprises the steps of preparing a pasty mixture by mixing in a predetermined amount of a liquid resin having a predetermined initial viscosity, a predetermined amount of a metal powder or a blend of metal and metal oxide powders, and inserting the pasty mixture between the mating weld surfaces of the aluminum articles. Only a small welding force and a low current will be required in producing a resistance weld connection between the aluminum articles with desired strength.