Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.
DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.
Diamonds possess significant hardness and durability; however, any attempt to deform them typically leads to brittle fracture. In this study, we comprehensively characterize nanoscale diamond at elevated temperatures, using a combination of experimental and molecular dynamic (MD) simulation approaches. We present the fabrication and compression testing of single crystal diamond < 100 > nanopillars fabricated by electron beam lithography and inductively coupled plasma etching to achieve, for the first time, a highly pristine diamond nanoarchitecture. Remarkably, our findings unveil a distinctive brittle-to-plastic transition in diamond behavior, occurring at approximately 550 °C. The fracture stress exhibited by these pristine nanopillars exceeds the strength reported previously in literature for < 100 > oriented diamond. Complementary MD simulations provide a deeper understanding of the underlying deformation mechanisms involved in brittle-to-plastic transition. The insights from this study offer novel pathways for advancing both the fabrication of pristine diamond nanoarchitectures and their strain engineering, with envisioned extreme high-temperature applications in diamond based micro- and nano- electromechanical systems (MEMS/NEMS) and micro/nanomechanics.
Aleksandra Radenovic, Evgenii Glushkov
William Curtin, Alireza Ghafarollahi