The role of filler wire and scanning strategy in laser welding of difficult-to-weld aluminum alloys

Abstract

Abstract Laser welding of dissimilar aluminum alloys gained an increased interest in the last few years, especially for the production of lightweight components. Pores and crack formation is one of the most critical factors to be taken into consideration in this type of application, in particular when one or more parts are produced by means of die casting or additive manufacturing. Current laser systems offer several methods for defects reduction and process control and optimized process’s strategies must be correlated to key-weld factors. In light of these factors, the current paper discusses the lap-joint welding of AA6082 sheets with AlSi10Mg ones produced additively in a configuration that is typical for the manufacture of battery housing for the e-mobility industry. Both autogenous laser welding and laser welding with filler wire are investigated, along with the potential advantages of using a wobbling scanning strategy, in order to understand the impact of process strategies on weld bead quality. The importance of process parameters is pointed out for any of the aforementioned strategies, with special emphasis on defects, weld bead chemical composition, joint morphology and dilution between involved materials. The findings demonstrated that, by selecting a welding with wire and active wobbling, high-reflection alloys can be welded correctly and with a good tolerance on the process parameters, but autogenous high-productivity welding can also be considered in linear scanning conditions with a specific optimization of the process parameters.