Sheared solid materials

Ōnuki, Akira; Furukawa, Akira; Minami, Akihiko

doi:10.1007/bf02704575

Cited by 14 publications

(6 citation statements)

References 47 publications

(66 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…3À6 Many theoretical 7À10 and experimental 11À14 works have been made in approach to find this "hidden order parameter" in glass state. Free-volume theory, 15 mode-coupling theory, 16 energy-landscape theory, 2, 17 and spin-glass model 18 are few examples of such works that have attempted to explain glass transition, yet had not grasped the complete concept. Over the years, researches concerning glass-transition have greatly advanced with the establishment of computer simulations.…”

Section: Introductionmentioning

confidence: 99%

Common Origin of Dynamics Heterogeneity and Cooperatively Rearranging Region in Polymer Melts

2011

View full text Add to dashboard Cite

If some supercooled liquids are cooled further, they freeze into a specific medium state with both properties of liquid-like structure and solid-like hardness, so-called “glass.” The fact that dynamics freeze drastically when there is only a slight change in static structure remains a mystery in solid-state physics. Recently, it has been reported that when a particular kind of glass-forming liquids with two order parameters are cooled rapidly, local crystalline orders with extremely slow dynamics start to emerge when approaching glass transition temperature. This result suggests a concept of “frustration to crystallization” as a physical picture of glass transition. On the other hand, although Adam–Gibbs theory has predicted the existence of cooperatively rearranging region (CRR) as the origin of extreme slowdown in dynamics, CRR is still no more than a hypothetical subsistent to explain the slow dynamics of glass transition. In this study, we found for the first time, local-bond orientational orders, “LBOOs,” which characterize glass transition in polymer melts, one of the most representative glass-forming liquids. Furthermore, we confirmed that monomers composed of LBOOs were concertedly vibrating and indicated that LBOOs can be identified as CRR. In other words, we were able to prove that the LBOOs we have discovered were consistent with both the physical picture of frustration to crystallization and Adam–Gibbs’ theory.

show abstract

Section: Introductionmentioning

confidence: 99%

Common Origin of Dynamics Heterogeneity and Cooperatively Rearranging Region in Polymer Melts

2011

View full text Add to dashboard Cite

show abstract

“…In our geometrically nonlinear approach the applied simple shear biases one of these modes and, as we have seen above, the two plastic "mechanisms" end up activated consecutively rather than simultaneously as the linearized theory (as well as classical CP) would suggest. Similar degeneracy occurs also in the case of triangular lattices if the configurational space is reduced to the plane tangent to the point T 0 as in [225].…”

Section: Ideal Shear Strengthmentioning

confidence: 58%

Discontinuous yielding of pristine micro-crystals

Salman¹,

Baggio²,

Bacroix³

et al. 2021

Comptes Rendus. Physique

View full text Add to dashboard Cite

We study the mechanical response of a dislocation-free 2D crystal under homogenous shear using a new mesoscopic approach to crystal plasticity, a Landau-type theory, accounting for the global invariance of the energy in the space of strain tensors while operating with an infinite number of equivalent energy wells. The advantage of this approach is that it eliminates arbitrariness in dealing with topological transitions involved, for instance, in nucleation and annihilation of dislocations. We use discontinuous yielding of pristine micro-crystals as a benchmark problem for the new theory and show that the nature of the catastrophic instability, which in this setting inevitably follows the standard affine response, depends not only on lattice symmetry but also on the orientation of the crystal in the loading device. The ensuing dislocation avalanche involves cooperative dislocation nucleation, resulting in the formation of complex microstructures controlled by a nontrivial self-induced coupling between different plastic mechanisms.

show abstract

“…The holes are treated here to be static and their abundance is inferred invoking the thermodynamic extremum principle. Understanding the slow dynamics of the holes or the associated free volume with the help of the generalized hydrodynamic models [53] will be of interest for future studies.…”

Section: Discussionmentioning

confidence: 99%

Characteristic temperatures of glassy behaviour in a simple liquid

Singh¹,

Das²

2007

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

A model for the metastable liquid in terms of holes present in the amorphous structure is considered using the classical density functional theory (DFT). For a one component Lennard-Jones liquid we obtain the temperature dependence of the free volume v(f) in the metastable state. A temperature T(0), similar to that of the characteristic transition of the free volume theory, is identified by extrapolating v(f)(T) to zero. The Kauzmann temperature T(K) is also obtained here by extrapolating the entropy difference between the supercooled state and that of the crystal to zero. We compare the temperatures T(0) and T(K) obtained in our model with other two characteristic temperatures for glassy behaviour, namely (a) the dynamic transition temperature T(c) of the mode coupling theory (MCT) and (b) the glass transition temperature T(g) which was obtained by Leonardo et al (2000 Phys. Rev. Lett. 84 6054) from studying the violation of the fluctuation-dissipation theorem. All the four temperatures, obtained from independent routes, are located with respect to the melting temperature T(m) in a manner which is in agreement with experiments.

show abstract

Sheared solid materials

Cited by 14 publications

References 47 publications

Common Origin of Dynamics Heterogeneity and Cooperatively Rearranging Region in Polymer Melts

Common Origin of Dynamics Heterogeneity and Cooperatively Rearranging Region in Polymer Melts

Discontinuous yielding of pristine micro-crystals

Characteristic temperatures of glassy behaviour in a simple liquid

Contact Info

Product

Resources

About