Open AccessInvestigation and Optimization of Disk-Laser Welding of 1 mm Thick Ti-6Al-4V Titanium Alloy Sheets
Author(s) -
Fabrizia Caiazzo,
Vittorio Alfieri,
Ilaria Fierro,
Vincenzo Sergi
Publication year - 2014
Publication title -
advances in mechanical engineering/advances in mechanical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.318
H-Index - 40
eISSN - 1687-8140
pISSN - 1687-8132
DOI - 10.1155/2014/373561
Subject(s) - welding , materials science , laser beam welding , indentation hardness , ultimate tensile strength , butt joint , heat affected zone , titanium alloy , composite material , metallurgy , fusion welding , vickers hardness test , gas tungsten arc welding , titanium , alloy , arc welding , microstructure
Ti-6Al-4V joints are employed in nuclear engineering, civil industry, military, and space vehicles. Laser beam welding has been proven to be promising, thanks to increased penetration depth and reduction of possible defects of the welding bead; moreover, a smaller grain size in the fusion zone is better in comparison to either TIG or plasma arc welding, thus providing an increase in tensile strength of any welded structures. In this frame, the regression models for a number of crucial responses are discussed in this paper. The study has been conducted on 1 mm thick Ti-6Al-4V plates in square butt welding configuration; a disk-laser source has been used. A three-level Box-Behnken experimental design is considered. An optimum condition is then suggested via numerical optimization with the response surface method using desirability functions with proper weights and importance of constraints. Eventually, Vickers microhardness testing has been conducted to discuss structural changes in fusion and heat affected zone due to welding thermal cycles