The automotive and aerospace industries are utilising a higher proportion of composite materials, such as carbon fibre reinforced plastic (CFRP), to improve efficiency and reduce carbon emissions. Machining CFRP at the required productivity rates whilst maintaining material integrity is an ongoing challenge. Most mechanical and laser based techniques tend to reduce the material integrity at the required processing speeds. In particular, machining demonstrations with high power fibre and CO2 lasers produced large heat affected zones (HAZ). Alternative approaches utilising pulsed laser systems, in either the nanosecond or picosecond regime, reduce the HAZ but are either limited in average power or are complex and expensive systems. This project will aim to develop and demonstrate a laser-based technology that is capable of overcoming the current limitations.
High absorption in both the carbon fibres and the surrounding polymer matrix should ensure the CO2 laser is an ideal choice for machining composite material. Typical commercial CO2 lasers operate in a long pulse regime of >5µs at high average powers. However, the long pulses create a large HAZ which reduces the material integrity. Q-switched lasers with pulse widths <300ns are available but at typical average powers of <50W, insufficient for the required productivity.
This project will involve modelling and demonstrating novel techniques for short pulse generation and amplification in a cost effective, reliable CO2 laser architecture. A novel approach to resonator design will be employed to Q-switch a high power CO2 laser to produce >500W average power at pulse widths <250ns. Alternatively, a novel Q-switched source will be used to seed a MOPA using innovative extraction techniques to generate >500W average power at pulse widths <250ns.The final system will be used to develop optimised machining strategies for CFRP. This will be supported by modelling undertaken within the project.
The combination of high average power and short pulse width in a cost effective, reliable architecture is not currently available. By developing this laser system this project will generate a solution suited to machining a range of composite materials.
This project gives the student the opportunity to work within an established and dynamic development team that has a long history of innovation and success in creating products suited to a range of industries.
Luxinar (previously Rofin-Sinar UK) is one of the world’s leading designers and manufacturers of industrial lasers for machining and marking applications. We’re an innovative market leader in the development of world class industrial laser products. We take pride in having a collaborative approach with all our customers and partners. Our lasers drive future innovations in a range of industries.
The expansion of our product range and continuing growth of our company have created an opportunity for a self-motivated, innovative individual to take on this Engineering Doctorate project, and thereby join our Laser and Optics Group designing and developing Solid-State and CO2 lasers.
The company offers a stimulating and satisfying environment for personal growth & career development.
Minimum 1st Class BSc / 2:1 MPhys or equivalent in Physics or an optics/ photonics related subject
Has practical experimental experience
Able to work within a diverse team
Has experience of modelling complex systems
Has previous laser technology/ processing experience
Has undertaken some previous research