Experimental study of W–Eurofer laser brazing for divertor application

This work can be considered as a preliminary evaluation of the potential of laser brazing for joining tungsten based alloys to reduced activation ferritic–martensitic steels (Eurofer). Brazing of tungsten and EUROFER alloys using a 55Ni–45Ti alloy as a brazer and a high power diode laser (HPDL) as a power source has been investigated. The brazed joints showed solidified pools with good superficial aspect and a high degree of wettability with the both parent sheets, presumably because of the active effect of titanium. Metallurgical brazeability was investigated and nanoindentation measurements were done to evaluate local hardening and stiffness effects associated to dilution phenomena.

► Laser brazing system as a suitable technique to joint W and Eurofer alloys.
► High residual stresses at the bonding were produced.
► Laser brazing of powder metallurgy W alloys added porosity in the solidified pool.
► The CSM methodology as a suitable technique to discriminate zones of welding joints.