In this study, the ideal strength of β-silicon nitride was calculated using a first-principles molecular dynamics method. The stress-strain curve of β-silicon nitride was calculated from simulations of uniaxial extension in the [100] and [001] axial directions, and an ideal tensile strength of ∼72.2 and ∼75.0 GPa, respectively, was obtained. In addition, the elastic constants were determined, along the two principle axial directions, [100] and [001], and values of ∼559 and ∼403 GPa, respectively, were obtained. The elastic constant results were found to be in reasonable agreement with existing data.

• Received 12 April 2001

DOI:https://doi.org/10.1103/PhysRevB.64.172102