High deposition rate welding with a laser line optics with the laser-assisted double-wire deposition welding process with nontransferred arc

Laser-assisted double-wire welding with a nontransferred arc is used for cladding workpieces. The wire material is melted by an arc and dropped onto the substrate, where a laser beam is oscillated by a galvanometer scanner to achieve bonding of the melt with good contact angles that do not result in undercuts. In this study, the galvanometer scanner was replaced by a beam shaping optics generating a line with a width of 1.2 mm and a length of 9.1 mm. Based on Design of Experiments, the laser power was varied in a range from 1500 to 2000 W and the welding speed in a range from 600 to 800 mm/min. Single weld beads of AISI 316L were welded onto a mild steel of AISI 1024 according to a full factorial design at three repetitions per parameter set. The paper examines whether the contact angles of the weld beads produced with the line optics are comparable to those obtained by oscillating the laser beam. In addition, the dilution of the material with the substrate was determined in micrographs. The results show that the bonding to the substrate can be achieved. The parameter window for the laser power with beam shaping line optics is different from that with the oscillated laser beam. The required laser power is 1.5–2 times greater.