### Abstract

A two-dimensional finite element model is used to investigate compressive loading of a brittle ceramic. Intergranular cracking in the microstructure is captured explicitly by using a distribution of cohesive interfaces. The addition of confining stress increases the maximum strength and if high enough, can allow the effective material response to reach large strains before failure. Increasing the friction at the grain boundaries also increases the maximum strength until saturation of the strength is approached. Above a transitional strain rate, increasing the rate-of-deformation also increases the strength and as the strain rate increases, fragment sizes of the damaged specimen decrease. The effects of flaws within the specimen were investigated using a random distribution at various initial flaw densities. The model is able to capture an effective modulus change and degradation of strength as the initial flaw density increases. Effects of confinement, friction, and spatial distribution of flaws seem to depend on the crack coalescence and dilatation of the specimen, while strain-rate effects are result of inertial resistance to motion.

Original language | English (US) |
---|---|

Pages (from-to) | 2618-2641 |

Number of pages | 24 |

Journal | Journal of the Mechanics and Physics of Solids |

Volume | 56 |

Issue number | 8 |

DOIs | |

State | Published - Aug 1 2008 |

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### All Science Journal Classification (ASJC) codes

- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering

### Cite this

*Journal of the Mechanics and Physics of Solids*,

*56*(8), 2618-2641. https://doi.org/10.1016/j.jmps.2008.03.009

}

*Journal of the Mechanics and Physics of Solids*, vol. 56, no. 8, pp. 2618-2641. https://doi.org/10.1016/j.jmps.2008.03.009

**Computational micromechanics of dynamic compressive loading of a brittle polycrystalline material using a distribution of grain boundary properties.** / Kraft, R. H.; Molinari, J. F.; Ramesh, K. T.; Warner, D. H.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Computational micromechanics of dynamic compressive loading of a brittle polycrystalline material using a distribution of grain boundary properties

AU - Kraft, R. H.

AU - Molinari, J. F.

AU - Ramesh, K. T.

AU - Warner, D. H.

PY - 2008/8/1

Y1 - 2008/8/1

N2 - A two-dimensional finite element model is used to investigate compressive loading of a brittle ceramic. Intergranular cracking in the microstructure is captured explicitly by using a distribution of cohesive interfaces. The addition of confining stress increases the maximum strength and if high enough, can allow the effective material response to reach large strains before failure. Increasing the friction at the grain boundaries also increases the maximum strength until saturation of the strength is approached. Above a transitional strain rate, increasing the rate-of-deformation also increases the strength and as the strain rate increases, fragment sizes of the damaged specimen decrease. The effects of flaws within the specimen were investigated using a random distribution at various initial flaw densities. The model is able to capture an effective modulus change and degradation of strength as the initial flaw density increases. Effects of confinement, friction, and spatial distribution of flaws seem to depend on the crack coalescence and dilatation of the specimen, while strain-rate effects are result of inertial resistance to motion.

AB - A two-dimensional finite element model is used to investigate compressive loading of a brittle ceramic. Intergranular cracking in the microstructure is captured explicitly by using a distribution of cohesive interfaces. The addition of confining stress increases the maximum strength and if high enough, can allow the effective material response to reach large strains before failure. Increasing the friction at the grain boundaries also increases the maximum strength until saturation of the strength is approached. Above a transitional strain rate, increasing the rate-of-deformation also increases the strength and as the strain rate increases, fragment sizes of the damaged specimen decrease. The effects of flaws within the specimen were investigated using a random distribution at various initial flaw densities. The model is able to capture an effective modulus change and degradation of strength as the initial flaw density increases. Effects of confinement, friction, and spatial distribution of flaws seem to depend on the crack coalescence and dilatation of the specimen, while strain-rate effects are result of inertial resistance to motion.

UR - http://www.scopus.com/inward/record.url?scp=44949254810&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=44949254810&partnerID=8YFLogxK

U2 - 10.1016/j.jmps.2008.03.009

DO - 10.1016/j.jmps.2008.03.009

M3 - Article

AN - SCOPUS:44949254810

VL - 56

SP - 2618

EP - 2641

JO - Journal of the Mechanics and Physics of Solids

JF - Journal of the Mechanics and Physics of Solids

SN - 0022-5096

IS - 8

ER -