Dual Focus Nd:YAG Laser Welding of Titanium Alloys

Dual focus Nd:YAG laser welding has been considered as a method to reduce the formation of porosity in titanium alloy laser welds. The effects of the foci orientation, foci separation, welding speed and power distribution ratio on the resulting porosity have been examined using response surface methodology. Both transverse and in-line foci orientations, with controlled foci separations and welding speeds, can be used to establish a stable keyhole and vapour plume regime, promoting low porosity welds. The weld metal porosity levels can be reduced to within levels stipulated in stringent aerospace weld quality criteria.