Product Code: PIC2008_603

A Comparative Study of Single Mode Fibre Laser and Nd:YAG Laser Welding of Ti-6Al-4V
Authors:
Hui-Chi Chen, The University of Manchester; Manchester Great Britain
Andrew Pinkerton, The University of Manchester; Manchester Great Britain
Jonathan Blackburn, Twi Ltd; Cambridge Great Britain
Lin Li, The University of Manchester; Manchester Great Britain
Paul Hilton, Twi Ltd; Cambridge Great Britain
Presented at PICALO 2008

In the past ten years, fibre laser systems have been developed intensively and can now be obtained commercially for industrial use. The fibre laser has been recognised as one of the laser types with most potential for the future but little quantitative evaluation of their performance against that of more traditional lasers has yet been performed for materials such as titanium. This study compares fibre and lamp pumped Nd:YAG rod laser welding of the Ti-6Al-4V alpha-beta alloy, which is widely used in the chemical, transportation, aerospace and medical industries due to its high strength-to-weight ratio and corrosion resistance. Differences in the extent of the fusion zone, porosity content, microstructures, mechanical properties, and corrosion resistance of 2 mm thick plates butt welded with a 1 kW single mode fibre laser and a Nd:YAG laser are investigated and compared. Findings are interpreted with the aid of moving source, three dimensional finite element simulations of the process. The work indicates that while the basic mechanisms are the same the superior beam quality and other properties of a fibre laser beam offer several advantages.