| A new special mechanism of crack generation in single-phase crystalline, nanocrystalline and metal-ceramic nanocomposite solids deformed at ultrahigh stresses is suggested and theoretically examined. Crack generation is preceded by homogeneous formation of a nanoscale configuration of three non-crystallographic partials whose Burgers vector magnitudes continuously grow during the formation process at high shear stresses. Then a crack is generated at the dislocation with the largest Burgers vector magnitude. It is shown that cracks can be effectively generated by this mechanism in Ni (nickel), 3C-SiC (the cubic phase of silicon carbide) and metal-ceramic nanocomposites deformed at ultrahigh stresses. |
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