Technological plasmas are gases that contain electrically charged particles. This feature helps to drive chemical reactions. As a result, such plasmas are often used to clean, etch or modify material surfaces. “We wanted to take this method a step further,” explains 3D Cer-Met project coordinator Allan Matthews, professor of surface engineering and tribology at the University of Manchester in the United Kingdom. “Our aim in this project was to use plasmas to convert thin-walled metals, such as aluminium foil, into ceramic phases. What this means in practice is creating 3D thin-walled components that behave predominantly as ceramics since they are lightweight and chemically stable. However, they retain the strength of a metal core.” Matthews was confident that this method could open the door to the development of new products as diverse as healthcare devices and airplane/automotive parts.
Flexible 3D components
The 3D Cer-Met project was launched in January 2019 to investigate how this process could be achieved. It builds on the fundamental work carried out during the ERC-funded IMPUNEP project, which focused on the study and use of plasma-based processes. “This project took this research to the next stage,” says Matthews. “We needed to learn how to control the process, so that the growth rate of the new ceramic phase was uniform across a complex 3D-shaped surface.” Achieving this would not have been possible without an in-depth understanding of the specific characteristics of converting metals into ceramics. For this, the research team had to develop new research methods. “This work enabled us to demonstrate the feasibility of our approach,” notes Matthews. “We created lab-scale prototypes of complex-shaped thin-walled ceramic-metal composites. We also developed an understanding of how to scale up the process, and transfer this to new shapes and substrate materials.” The end result is that the team was able to demonstrate that the creation of uniform ceramic layers on the surfaces of complex metallic substrates was possible.
New engineering possibilities
The key advantage of the 3D Cer-Met approach is that it opens up the possibility of creating thin-walled structures with complex shapes. These components are highly resistant to attack by aggressive acidic compounds, and are highly tolerant to both low and high temperatures. “This would not have been possible by using conventional ceramic processing techniques,” adds Matthews. The knowledge gained through the 3D Cer-Met project will now be applied to scaling up the technology. “This process will greatly benefit the manufacturing sectors interested in producing and using ceramic and ceramic-metal components with enhanced structural and functional performance,” explains Matthews. “We are currently seeking collaborations with industrial partners who would be keen to implement these technological developments.” Matthews believes that the next logical step would be to carry out research on not only scaling up the technology but also making it more versatile. This would mean applying the technology to larger parts, as well as other metal substrates. “We can also see potential in digitalising this manufacturing technology,” he adds. “The work we have carried out, including numerical modelling and digital control of the process, lays a strong base for these activities.” Ultimately, Matthews is confident that this innovative manufacturing method will become a useful asset in a portfolio of future manufacturing technologies, offering an environment-friendly and resource-efficient solution.
3D Cer-Met, ceramics, metal, plasmas, aluminium, composite, substrates