Brazing project promises better aircraft engines

Brazing is a process used to join even dissimilar and difficult to weld materials, and is capable of creating complex, high strength joints. The process works by heating an alloy, known as a Brazing Filler Metal (BFM), between the parts to be joined, to form a bond.

However, as the range of applications in which these brazes are used increases, so to do the demands placed upon them, according to Dr Russell Goodall at Sheffield University, who is leading an EPSRC-funded project to develop BFMs with improved performance.

For example, the team, which also includes the UK Atomic Energy Authority, Rolls-Royce, Johnson Matthey and the University of Limerick, among others, hope to improve the strength of BFMs.

Joining two dissimilar metals with a different alloy can lead to the formation of metallic compounds, which can be brittle and limit the strength of the joint, said Goodall.

So the researchers will investigate a new type of alloy, known as a High Entropy Alloy, in which similar amounts of many elements are combined, unlike conventional materials that consist of one main solvent and small additions of other elements. By using these new alloys, they hope to create tougher, higher strength joints without the brittleness.