• SiC is an attractive material
    for many technologies that require high performance in
    extreme environments

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  • However, its utilization is often limited by a susceptibility to fracture

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  • Peridynamic approach enables a natural coupling of continuum mechanics modeling with atomistic simulation

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  • Hybrid Peridigm/ReaxFF modeling can be used to analyze crack formation at multiple scales 

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  • Peridigm geometry - bar with dimensions of 2 x 0.2 x 0.002 µm

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  • LAMMPS geometry - slab with dimensions of 200 x 200 x 20 Å

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  • An elastic correspondence model with a Verlet integration scheme was used in Peridig

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  • LAMMPS simulation was performed for 3C-SiC crystal using ab-initio based ReaxFF

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ReaxFF

  • Both HHM and LAMMPS started from the same initial configuration of a 3C-SiC slab with pre-crack

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  • Prescribed compression created a rough fracture surface, disordering atomic packing within a few atomic planes

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  • HHM predicted a linear crack propagation along shear stress direction that is ~45 degrees relative to the direction of tension

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  • LAMMPS yielded crack branching with an angle greater than 90 degrees, whereas experiments (Ramulu et al, 1985) showed smaller branching angles

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  • Disagreement is likely because HHM and LAMMPS account differently for reflections of waves from the boundaries, which control crack branching

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