Hybrid subtractive and additive laser materials processing for on-wing repair of safety critical aerospace components

In-situ (i.e. without dismantling) materials processing for the repair of geometrically complex aero-engine components can offer significant reductions in cost and lead-time when compared to off-site processing. The application of conventional materials processing (e.g., subtractive and additive) is, however, challenging considering the constraints imposed by the limited accessibility in the work environments often encountered in these scenarios that the end-effector delivery system (e.g. robot, mechanical arms) need to react to.

Laser surface engineering is an emerging technology for component repair (e.g., surface preparation) but not yet widely used in in-situ operations due to the large dimensions of the laser end effector as well as the presence of a heat affected zone where the material microstructure is changed.

The project aims to develop innovative hybrid laser beam processing (surface machining and deposition) methods and miniaturised device that will enable the surface preparation and repair of components while the engine is on-wing thus to enable timely cost effective repair and maintenance activities. A novel system for performing in-situ micro-machining and thermal barrier coating (TBC) deposition of aero-engines for repair applications will be developed.

An in-depth understanding of the interaction between the laser beam and the target surface will be studied so that surface can be prepared at high integrity to enable the deposition of TBC. Further materials processing activities will be carried out succession of 3D movements of the disassembled/assembled aeroengine part; this will be done by CAD modelling of the part and engine workspace so that spatial restrictions on part handling can be assessed.

A miniaturised laser end effector will be developed which will be attached to a continuum robot for in-situ aeroengine component repair.

This invention will enable maximising aircraft operational availability at the lowest possible through-life cost, and help anticipate and adapt to future requirements through substrative-additive repairs of high-value components.

This is a strategical project which will be partially sponsored by our current industry partners, i.e., Rolls-Royce, and the outcome will be employed by the industry for the on-wing repair of aeroengine component.