A novel approach to manufacturing lasers using ultrafast laser welding

Lead Research Organisation: Heriot-Watt University
Department Name: Sch of Engineering and Physical Science


This is a PhD research project in Physics. Ultrafast (picosecond, femtosecond) pulsed lasers have enabled welding processes to directly join highly dissimilar materials combinations (e.g. glass and metal). Such welding was previously thought to be impossible due to the very large difference in thermal expansion coefficients and hence thermally-induced cracking. From initial proof-of-concept experiments, Heriot-Watt have been working with Leonardo MW to convert the process into a robust manufacturing process, with a particular focus on welding borosilicate glass to Aluminium alloy Al6082. This industry-sponsored PhD project will build on this earlier research, focused on the application of such processes to the manufacture of a laser system. The use of this technology has important advantages, in particular removing the requirement for adhesives within the laser cavity. The proposed welding approach will also help to convert laser manufacturing from a skilled assembly process to a much lower cost automated manufacturing process.

Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/R511948/1 01/11/2017 31/10/2022
1963753 Studentship EP/R511948/1 01/10/2017 30/06/2021 Samuel Hann
Description The stress induced birefringece of welded N-BK7 to Al6082 has been investigated and shown to have a minimal effect on propagating light within the clear aperture of the glass samples using appropriate laser welding parameters. This completes objective 3 of the awards original objectives and makes objective 4 redundant which was to find a means of minimising the stress in the weld through varying the weld pattern as the stress was expected to be very significant but has been shown to not be the case.

Ultrashort pulse laser welding method has been expanded to successfully weld YAG laser crystals to an aluminium silicon heatsink material (AlSi) which completes objective 2 of the awards original objectives.
Exploitation Route Using the knowledge gained from this research to further develop the direct bonding of optical elements with ultrashort pulse laser welding, in particular the direct bonding of laser crystals such as Nd:YAG to an AlSi heatsink.
Sectors Aerospace, Defence and Marine,Manufacturing, including Industrial Biotechology

Description Leonardo Studentship
Amount £33,250 (GBP)
Organisation Leonardo MW Ltd. 
Sector Private
Country United Kingdom
Start 10/2017 
End 03/2021
Description Leonardo Studentship 
Organisation Leonardo MW Ltd.
Country United Kingdom 
Sector Private 
PI Contribution We are researching a direct bonding method which is of interest to them in their manufacturing supply chain.
Collaborator Contribution Technical discussions and assistance with commercially relevant aspects of the project.
Impact Direct Funding Assistance
Start Year 2017
Description Lab Tours 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Lab tours showing guests from industry, undergraduate students and researchers/professors around our facilities and explaining and discussing our research and its intended impact on industry.
Year(s) Of Engagement Activity 2017,2018,2019,2020