Nano-structure of coated voids in Al-(Cu-)Sn alloys

Voids are fundamental defects in materials. They are generally seen as detrimental to materials properties but have recently been found to have promising applications in optoelectronics and plasmonics. Voids in aluminium are of particular research significance, not only because aluminium is one of the most used metals but also because it is particularly prone to void formation. This thesis focuses on nanoscale voids in aluminium alloys. Their evolution has been explored under a range of heat treatments. Their sizes, morphologies and surface structure have also been characterised. The formation of intriguing tubular-shaped voids has been explained and these voids have allowed a new depth gauging method using electron diffraction to be developed.