Laser welding nickel and titanium-based aerospace alloys requires control of the weld geometry and weld microstructure, including minimizing porosity and controlling grain size. In many aerospace applications, the fatigue properties of the weld are a critical design criteria. For this reason, designers nearly always specify that the weld surfaces be convex, or slightly crowned, to create a reinforcement of the weld.

To achieve this, a 1.2 mm diameter filler wire is used in the automated process or you use a wobble welding head. Addition of the filler wire to a butt joint leads to a consistent crown on both the top and bottom weld bead. The selection of the alloy of the wire also contributes to the weld’s mechanical properties by ensuring a sound microstructure of the weld.