Investigation on Ti6Al4V laser welding using statistical and Taguchi approaches

Ti6Al4V is presently one of the most widely used titanium alloys, accounting for more than 50% of all titanium tonnage in the world, and to date no other titanium alloy has been a threat to its dominant position. Laser welding of Ti6Al4V is a major issue in the automotive and aerospace industries. In this paper, both CO2 and diode laser welding processes were investigated for Ti6Al4V alloy sheet joining using either lap or butt configurations. Artificial neural networks (ANN) processed the data coming from the experimental trials. The aim was to interpolate the database in order to form a suitable database for the analysis of the variance (ANOVA) and the Taguchi analysis of the means. The ANOVA has the merit of being able to be validated on a statistical basis while the Taguchi engineering approach has the ability of maximizing the information coming from a small database of data. Therefore, reliable and valuable information over the ranges of the processes investigated was individuated from a limited number of trials.