Descrizione del progetto
Valutare la durabilità dei nanomateriali a velocità di deformazione elevate
La nanoindentazione è l’ultima tecnologia che permette ai ricercatori di misurare le proprietà meccaniche di un materiale su scala nanometrica e micrometrica. Essa può tuttavia determinare le proprietà meccaniche solo per carichi controllati e non per urti o collisioni. Attualmente, i ricercatori sono in grado di riprodurre velocità di deformazione elevate solo su campioni grandi e omogenei. Il progetto NanoHighSpeed, finanziato dall’UE, si propone di far progredire la nanoindentazione in un nuovo strumento per esperimenti a velocità di deformazione elevata, grazie ai progressi dell’hardware e dei metodi sperimentali. Il nuovo processo sarà in grado di caratterizzare i materiali a velocità di deformazione milioni di volte superiori e su scale milioni di volte più piccole.
Obiettivo
For a sustainable economy, it is paramount to create robust, durable products. In the case of mobile phone displays, cutting tools and other products subjected to impact loading, this means finding ways to avoid brittle failure at high stain rates. This is currently difficult, since little to no fundamental understanding of the deformation mechanisms at high strain rates exists. This is largely owing to the fact that no methods are available for nanoscale investigations. By developing nanoindentation into a new tool for high strain rate testing, we will achieve a groundbreaking improvement of the spatial resolution of high strain rate mechanical testing by 10^6. This extraordinary improvement will be possible through simultaneous advances in hardware and experimental methods.
This new nanoscale approach will enable a breakthrough in the fundamental understanding of the mechanical behavior of materials at high strain rates down to their constituent microstructural elements. We will isolate single grain boundaries and measure their individual contribution to strength and embrittlement as a function of strain rate, crystal structure and grain boundary energy. The local resistance to dislocation transmission, migration and fracture will be correlated to the overall Hall-Petch strengthening behavior of the polycrystal. The payoff will be a better understanding and predictability of embrittlement events at high strain rates.
A second breakthrough will be made possible in understanding the interplay between plasticity and brittle fracture at high strain rates in some of the technologically most important hard coatings, including toughened glass used in mobile phone screens and TiAlN based coatings, commonly used in tooling. We will examine the recent hypothesis of a possible regain in ductility and systematically investigate the influence of the microstructure and residual stress. This will open up new paths for optimizing the durability of future coating systems.
Campo scientifico
- engineering and technologymaterials engineeringcrystals
- agricultural sciencesagriculture, forestry, and fisheriesagriculturegrains and oilseeds
- engineering and technologymaterials engineeringcoating and films
- engineering and technologyelectrical engineering, electronic engineering, information engineeringinformation engineeringtelecommunicationsmobile phones
- social scienceseconomics and businesseconomicssustainable economy
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-STG - Starting GrantIstituzione ospitante
34125 Kassel
Germania