Welding of thick austenitic stainless steel using Nd:YAG -laser with filler wire and hybrid process

Abstract

Autogenous laser welding has shown many advantages over welding methods in numerous applications. However, there could be even more applications but according to the power levels of present high power lasers depth of penetration is limited. One way to overcome this limitation is to use multipass laser welding, in which narrow gap and filler wire is applied. By this process thick sections can be welded with smaller heat input and then smaller distortions and process seem to be very effective comparing traditional welding methods not only according to the narrower gap. Another way to increase penetration and fill the groove is using so called hybrid process, in which laser and GMAW are combined.In this study thick section austenitic stainless steel is welded using multipass technique with filler wire and also hybrid process. For narrow gap, groove angles of 8, 10 and 12 degrees are used with partially grooved V joint. Parameters, for example in filler wire feeding and placement of wire and arc are varied. Results of experiments are presented and phenomena of the process as well as reasons for weld defects are pointed out.Autogenous laser welding has shown many advantages over welding methods in numerous applications. However, there could be even more applications but according to the power levels of present high power lasers depth of penetration is limited. One way to overcome this limitation is to use multipass laser welding, in which narrow gap and filler wire is applied. By this process thick sections can be welded with smaller heat input and then smaller distortions and process seem to be very effective comparing traditional welding methods not only according to the narrower gap. Another way to increase penetration and fill the groove is using so called hybrid process, in which laser and GMAW are combined.In this study thick section austenitic stainless steel is welded using multipass technique with filler wire and also hybrid process. For narrow gap, groove angles of 8, 10 and 12 degrees are used with par...