Atomistic simulations of materials fracture and link between atomic and continuum length scales
- Argonne National Lab., IL (United States). Materials Science Div.
- Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Nuclear Engineering
The macroscopic fracture response of real materials originates from the competition and interplay of several atomic-scale mechanisms of decohesion and shear, such as interplanar cleavage and dislocation nucleation and motion. These phenomena involve processes over a wide range of length scales, from the atomic to the macroscopic. The authors briefly review the attempts to span these length scales in dislocation and fracture modeling by (1) fully atomistic large-scale simulations of millions of atoms or more, approaching the continuum limit from the bottom-up; (2) directly coupling atomic-scale simulations and continuum mechanics, in a top-down approach; and (3) by defining a set of variables common to atomistic simulations and continuum mechanics and feeding the results of atomistic simulations into continuum-mechanics models in the form of constitutive relations. For this latter approach, the authors discuss in detail the issues crucial to ensuring the consistency of the atomistic results and continuum mechanics. A case study of the constitutive-relation approach is presented for the problem of dislocation nucleation from a crack tip in a crystal under stress; a comparison of the results of atomistic simulations to the Peierls-Nabarro continuum model is made.
- Research Organization:
- Argonne National Laboratory (ANL), Argonne, IL
- Sponsoring Organization:
- USDOE, Washington, DC (United States); North Atlantic Treaty Organization, Brussels (Belgium); National Science Foundation, Washington, DC (United States); Consiglio Nazionale delle Ricerche, Rome (Italy)
- DOE Contract Number:
- W-31109-ENG-38
- OSTI ID:
- 616483
- Journal Information:
- Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 3 Vol. 81; ISSN 0002-7820; ISSN JACTAW
- Country of Publication:
- United States
- Language:
- English
Similar Records
Atomistic simulation of dislocation nucleation and motion from a crack tip
Effect of crack geometry on dislocation nucleation and cleavage thresholds