### Abstract

Original language | Undefined/Unknown |
---|---|

Article number | 174209 |

Number of pages | 5 |

Journal | Physical Review B (Condensed Matter) |

Volume | 73 |

DOIs | |

Publication status | Published - 24 May 2006 |

### Keywords

- shear rate
- shear stress
- yield stress
- flow curves

### Cite this

*Physical Review B (Condensed Matter)*,

*73*, [174209]. https://doi.org/10.1103/PhysRevB.73.174209

}

*Physical Review B (Condensed Matter)*, vol. 73, 174209. https://doi.org/10.1103/PhysRevB.73.174209

**Yield stress discontinuity in a simple glass.** / Varnik, F.; Henrich, O.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Yield stress discontinuity in a simple glass

AU - Varnik, F.

AU - Henrich, O.

PY - 2006/5/24

Y1 - 2006/5/24

N2 - Large scale molecular dynamics simulations are performed to study the steady state yielding dynamics of a well established simple glass. In contrast to the supercooled state, where the shear stress, $\sigma$, tends to zero at vanishing shear rate, $\gammadot$, a stress plateau forms in the glass which extends over about two decades in shear rate. This strongly suggests the existence of a finite dynamic yield stress in the glass, $\sigma^+ (T) \equiv \sigma(T; \gammadot \to 0) >0$. Furthermore, the temperature dependence of $\sigma^+$ suggests a yield stress discontinuity at the glass transition in agreement with recent theoretical predictions. We scrutinize and support this observation by testing explicitly for the assumptions (affine flow, absence of flow induced ordering) inherent in the theory. Also, a qualitative change of the flow curves enables us to bracket the glass transition temperature $T_c$ of the theory from above and (for the first time in simulations) {\it from below}. Furthermore, the structural relaxation time in the steady state behaves quite similar to the system viscosity at all studied shear rates and temperatures.

AB - Large scale molecular dynamics simulations are performed to study the steady state yielding dynamics of a well established simple glass. In contrast to the supercooled state, where the shear stress, $\sigma$, tends to zero at vanishing shear rate, $\gammadot$, a stress plateau forms in the glass which extends over about two decades in shear rate. This strongly suggests the existence of a finite dynamic yield stress in the glass, $\sigma^+ (T) \equiv \sigma(T; \gammadot \to 0) >0$. Furthermore, the temperature dependence of $\sigma^+$ suggests a yield stress discontinuity at the glass transition in agreement with recent theoretical predictions. We scrutinize and support this observation by testing explicitly for the assumptions (affine flow, absence of flow induced ordering) inherent in the theory. Also, a qualitative change of the flow curves enables us to bracket the glass transition temperature $T_c$ of the theory from above and (for the first time in simulations) {\it from below}. Furthermore, the structural relaxation time in the steady state behaves quite similar to the system viscosity at all studied shear rates and temperatures.

KW - shear rate

KW - shear stress

KW - yield stress

KW - flow curves

UR - https://journals.aps.org/prb/

U2 - 10.1103/PhysRevB.73.174209

DO - 10.1103/PhysRevB.73.174209

M3 - Article

VL - 73

JO - Physical Review B (Condensed Matter)

JF - Physical Review B (Condensed Matter)

SN - 0163-1829

M1 - 174209

ER -