Investigation Of Laser-Arc Hybrid Welding On Austenitic Stainless Steel

With the development of technology, a new and advanced welding method named laser welding came out in 20th century. It has more merits than the conventional welding methods, such as the faster welding speed, the smaller distortion after welding and the deeper penetration etc. However it can not be widely used owing to the excessive cost of laser producing, the smaller fitting tolerance when butt welding and the poor welding efficiencies.In order to employ the laser welding more widely used in industry fields, W. Steen who was a famous English welding experts invented the laser-arc hybrid welding process in 1970's. Because of many merits of this welding method, it was very noticed by welding experts from many countries. After that, many types of hybrid welding were developed and they can all improve the welding qualities and efficiencies compared with the laser welding.Based on the achievements of other welding experts on hybrid welding, we studied the YAG laser-MAG and YAG laser-PAW hybrid welding and the welding material was 1Cr18Ni9Ti austenitic stainless steel. The influences of laser power, welding speed, arc current to the penetration and bead width were studied, and compared with the laser welding and arc welding. And the microstucture, microhardness, tensibility, bendness, fatigueness of butt welding of YAG laser-PAW hybrid welding were studied.It was showed that compared with the laser welding and arc welding, the two hybrid welding processes can improve the penetration, bead width and the welding speed. In YAG laser-MAG hybrid welding process, the welding speed can be double of laser welding's and three times of MAG welding's. In YAG laser-PAW hybrid welding process, the tensibility, bendness, fatigueness of butt welding was almost the same of laser welding. So, it can be concluded that hybrid welding is a promising welding method.