Materials Gateway
Resource Center
Login button
 Open/CloseSend Us Your Feedback

A Molecular Dynamics Simulation of High Strain-rate Deformation in Nanocrystalline Silicon Carbide

Author(s):
Yifei Mo, Izabela Szlufarska

Multi-million atom molecular dynamics simulations of tensile testing have been performed on nc-SiC. Reduction of grain size promotes simultaneous enhancement of ductility, toughness, and strength. Simulations show that intergranular fracture is the failure mechanism preceded by atomic level necking. Since diffusion prevents premature cavitation and failure, it sets an upper limit on high strain-rate deformations of ceramics. We report a non-diffusional mechanism for suppressing premature cavitation, which is based on unconstrained plastic flow at grain boundaries. In addition, based on the composite¡¯s rule of mixture, we estimate Young¡¯s modulus of random high-angle grain boundaries in nc-SiC to be about 130 GPa. The effect of temperature and strain rate on mechanical properties is studied.

Member Price: $0; Non-Member Price: $25.00
Track ID:
Paper #: 1021-HH04-02
DOI: