Project background
The production cost and/or weight of many aerospace structures made from titanium alloys would benefit from developments in, and a wider understanding of, what laser welding and its associated technologies are capable of when applied to titanium alloys and metal matrix composites (MMCs).
Appropriately developed laser welding procedures could, for example, be used to replace sealed and riveted assemblies (such as has already been done for some aluminium structures). With the inclusion of MMCs in to certain structures, greater weight savings could also be made, without compromising performance.
Work programme
Following an initial definition of their requirements, TWI is assisting a number of UK companies supplying aircraft and helicopter parts, choosing suitable welding equipment supported by IPG Photonics, and then developing specific laser beam welding procedures for their applications.
The process tolerances of the welding approaches being developed for different thicknesses of joints between Ti alloys, or between Ti alloys and Ti MMCs, are being examined and, along with the MTC and NITC, the resulting qualities and properties of the welds are then being evaluated.
TWI is also developing gas shielding and weld plume control solutions complementary to certain application needs, in line with fixture innovations being developed at the MTC.
With the possibility of fibre-delivered, robotic laser welding of certain parts, suitable path programs, access issues, etc, are also being modelled, offline, by the NITC, ahead of case study demonstrations planned towards the end of the project.
These will involve thin section stake welding as a means of replacing riveting in firewalls and bulkheads, thin section butt welding for leading edge structures, and thicker section butt welding for connections between MMC tubes and Ti alloy end fittings.
For further information about this project and the opportunities it can bring your company in terms of innovations in fixtures, laser welding, gas shielding and non-destructive inspection, please email contactus@twi.co.uk for further details.