Working under Professor Bill O’Neill, a team of researchers is investigating a number of different approaches to manufacturing metal items without the use of moulds and molten metal. This is important for the repair of existing metal objects, coating one metal with a metal of different melting point, as well as allowing the use of metal alloys which are difficult to melt. Matthew and Andrew are focused on techniques for spraying metal powder at 1000 ms-1 onto metal surfaces, laying down a dense layer of the new material.
Existing techniques of this kind have proven to be very expensive, and the team’s use of lasers aims to improve the cost-effectiveness of the method. Their techniques allow a range of unique approaches, including laying down multiple thin layers of different metals, and the use of metals such as steel and titanium which are easily oxidised by melting. In the future, mixtures of metals and ceramic-metal combinations may also be used as coatings. In addition the technique results in a work-hardened metal coating, giving it different physical characteristics than would be achieved by spraying a molten coating into a mould.
Two main areas have so far been identified for this technique, for the repair of high-value metal components such as gear teeth or turbine blades, and for the surface coating of cheap metal components with a more expensive metal with different properties.
The i-Team’s challenge will be to identify and recommend specific applications within these areas which can most benefit from the metal spraying technique, to allow the technique to be developed appropriately for real-world use.