Laser beam welding of titanium - A comparison of CO2 and fiber laser for potential aerospace applications

The Laser welding process is increasingly being considered for joining titanium alloy airplane structures and also for manufacture, repair and overhaul of titanium aeroengine components. Recent advancement in gas and solid state laser technology has resulted in the availability of higher beam quality Lasers which can produce narrow welds with low heat input and high weld speeds. This paper describes a study of Laser welding of the Titanium alloys Ti6-4 and Ti5553 using two types of high power Laser - a CO2 Slab Laser and a Ytterbium-Fiber Laser. The differences between both Lasers and their effect on weld quality and performance will be explained. The weld results have been evaluated referring to AWS weld quality standards, with particular reference to porosity appearance and weld profile. In addition, micro hardness measurements and tensile test data will be shown.