Atomistic Mechanisms in Silicon Carbide Nanostructures

An overview of recent atomistic simulations and experiments on silicon carbide (SiC) nanostructures is presented. A focus is given to the discussion of novel atomistic mechanisms active in the narrow length scale of nanostructures. Those include mechanisms in nanocrystalline SiC, SiC nanofilms, and SiC nanowires. The reviewed investigations on nanocrystalline SiC show an unusual simultaneous increase in toughness and strength on grain size reduction and a crossover in the mechanical response under indentation. A study of SiC nanofilm under shock conditions suggests an unexpected mechanism for brittle fracture generation based on nanoductility. Studies of SiC nanowires reveal new damage mechanisms including induced dynamic amorphization, present at both low and extreme strain rates, large plastic deformation and super-plasticity at low temperature, and reversible structural transformations under uniaxial strain. The reviewed investigations highlight how intriguing can be the behavior of materials at the nanoscale when compared to their relatively known bulk counterparts.