Laser welding of Waspaloy(R) sheets for aero-engines

Laser welding techniques have been characterised for various materials, using different laser sources. However, such research has not been performed on superalloys used in aero-engine fabrication and maintenance. In this paper, the laser weldability of a nickel-base alloy, Waspaloy, is investigated using CO2 and Nd:YAG lasers. The results indicate that the microfissures that occur at the grain boundary in the heat-affected zone linked with the fusion zone are reduced by decreasing the welding speed and the material thickness. Metallurgical analysis reveals fine Ni-3(AlTi) precipitation and MC carbides in the fusion zone. A casing for aero-engines made of 2 mm thick Waspaloy sheets has been assembled using laser cutting and welding technology. (C) 1997 Elsevier Science S.A.