Investigation on laser welding of Ti-6Al-4V plates in corner joint

Abstract

The article deals with laser beam welding of Ti-6Al-4V plates for aerospace applications. A number of trials are conducted to weld 3-mm-thick plates in corner joint configuration; a specific device for clamping and shielding to prevent oxidation is used. Autogenous welding is investigated, the joint being accessed from the outside, as a butt-welded corner joint. Referring to international standards, the results are first discussed in terms of geometry of the welding bead in the cross-section since titanium alloys are reported to be notch sensitive. Moreover, microstructure and microhardness are investigated. An optimum processing condition is suggested in order to perform laser beam welding with minimal undercut and porosity.