Iraitz Arrospide.jpg

Leon Proud

Project Title: Cryogenic and CO2 Coolants During Machining of Next-Generation Aircraft-Grade Materials

Academic Supervisor: Dr Tom Slatter

AMRC Supervisor: Dr Nikos Tapoglou

Industry Sponsor: AMRC

Hi everyone, I’m Leon an EngD student at the AMRC researching the impact of CO2 coolants for the machining of Biomedical/Aerospace materials. To begin, let me first extend my condolences that you’ve clearly had the misfortune of scouring the depths of the internet with such rigour to find yourself in the archives of the IDC website. Most people procrastinate on YouTube, Facebook, or Twitter, but in the spirit of Engineering you’ve landed here, which is, if not impressive, at least commendable.

To tell you a little about my work, my research is currently focused upon the use of external supercritical CO2 (scCO2) cooling as a sustainable alternative to emulsion-based coolant strategies. My work so far has largely focused upon the cryo-milling of Grade 2 commercially pure titanium (CP-Ti). Last year I conducted initial scoping trials to assess the baseline machinability of CP-Ti using generalised cutting and coolant conditions, whilst this year my intentions are to optimise the cutting parameter set to improve performance outcomes (of the scCO2 coolant strategy). The work is proving to be extremely interesting despite its challenges and hopefully I’ll be able to contribute towards increasing the understanding of the technology over the coming years.

Aside from engineering, I love sport, and play football, badminton, squash and golf regularly, I try to Ski once a year and get out on the motorbike when the weather permits. I’m also obsessed with guitar, so, needless to say, my neighbours are huge fans…

If you’d like to know anything else about my work, or you just want a chat please feel free to get in touch via email at: or


Proud, L., Tapoglou, N. and Slatter, T. 2022. 'A Review of CO2 Coolants for Sustainable Machining'. Metals 12:2, 283.

Read paper here