Atomistic-based predictions of crack tip behavior in silicon carbide across a range of temperatures and strain rates

The utility of silicon carbide (SiC) as an engineering material is often limited by its brittleness. This work attempts to better illuminate the key mechanisms associated with this property by studying crack tip behavior. A multipronged investigative approach is taken, utilizing direct molecular dynamics simulations with empirical potentials, analytic modeling and electronic structure calculations. This approach enables us (i) to make atomistic-based predictions of the key mechanisms that occur at a SiC crack tip across a wide range of temperatures and strain rates; and (ii) to better understand the strengths and deficiencies of these analysis tools for predicting fracture in covalently bonded materials.