Feasibility study of dissimilar metal joining by laser riveting of Ti-6Al-4V to AA6061.

Aluminum of cylindrical profile (of diameter 1–4 mm) was trailed by laser metal wire deposition for potential riveting applications. The rivet was built onto a Ti6Al4V substrate through a hole in an AA6061 sheet. The built feature was postprocessed by a high-frequency laser washing technique to obtain the desired finish. Parameter optimization has allowed increased productivity by almost seven times while achieving required wetting conditions and metallurgical properties. It is found that the quality (both morphology and metallurgy) of the laser rivet joint is highly dependent on the laser wash parameters. The rivet crown and welding areas improved by the postwash process were directly reflected in the microhardness and shear tests and increased by 90% and 62%, respectively, compared with those in an unwashed rivet. [ABSTRACT FROM AUTHOR]