This project with the acronym GB-CORRELATE is supported by an Advanced Grant for Gerhard Dehm by the European Research Council (ERC) and started in August 2018.
The project GB-CORRELATE explores the presence and consequences of grain boundary phase transitions (often termed “complexions” in literature) in pure and alloyed Cu and Al. If grain size gets smaller and smaller - like in nanocrystalline materials - the grain boundary (GB) volume can exceed several 10% of the total material volume and become a powerful lever to manipulate and set properties. The atomic coordination and chemistry of such GBs may undergo phase transitions, abrupt changes in structure and/or chemistry, which will impact the material behavior - like strength, thermal stability, electrical resistance – even for conventional materials. However, this interplay between GB phases and material properties is poorly understood. Experimentally, GBs are difficult to study - it needs atomic resolution and sensitivity with respect to chemistry to uncover their structure and possible complexions. In addition, it is unknown under which conditions phase transformations of GBs occur. A fundamental understanding requires atomistic modelling connected with smart experiments.