Lattice instability in β‐SiC and simulation of brittle fracture

摘要: Brittle fracture of β‐SiC (polytype 3C) under hydrostatic tension has been modeled by molecular dynamics simulation using an interatomic potential function that treats the solid as fully covalent. The critical stress at which lattice becomes structurally unstable is shown to agree quantitatively with predicted stability analysis based on elastic stiffness coefficients. instability mode spinodal (vanishing bulk modulus), and decohesion occurs spontaneous nucleation cracking {111} shuffle planes. Atomic relaxation newly generated cracked surfaces appears take place immediately following crack opening.