PSI - Issue 39

Larisa Stepanova et al. / Procedia Structural Integrity 39 (2022) 748–760 Author name / Structural Integrity Procedia 00 (2019) 000–000

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3. Discussion and results In this study, based on MD simulations, the stress intensity factors and higher order coefficients of the Williams - based approximation of the stress field for mixed mode loading for some values of the mixity parameter are obtained. The analytical solution for the higher order coefficients of the Williams series expansion for the stress field in an infinite plate with the central crack is used. A comparison of the near-crack tip stress fields obtained from atomistic simulations and continuum fracture theory is given in this paper. The decent atomistic simulations reveal that continuum mechanics can be applied at nanoscale. Good agreement of the stress is found on both levels of description. The applicability of linear elastic fracture mechanics in nanometer range close to crack tips in brittle materials is shown. 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