LIE HomeIssue Contents

Welding of Ti-6Al-4V Using a Fibre Laser, Part I: Investigation of the Process Characteristics
J. Iammi and J. Folkes

In this study the welding of Ti-6Al-4V alloy sheet with a high brightness fibre laser was investigated. The effect of process parameters including laser power, welding speed and shielding gas flow rate on the weld profile was determined. Suitable shielding conditions were also studied. The plasma/plume which occurred during the welding process has been observed and the black deposit formed using both argon shielding and helium shielding has been analysed. The microstructure and hardness of the welds were examined. The results indicated that laser power and the welding speed used have a significant effect on the weld profile due to the difference in heat input per unit weld length applied. The black deposit found during the welding process consisted of metallic atoms evaporated from molten pool and particularly the keyhole at high power densities. The particle size was smaller when using helium as opposed to argon, as a shielding gas.

Keywords: Ti-6Al-4V; fibre laser, welding, shielding gas, black deposit, plasma/plume

Full Text (IP)