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Collective rearrangement at the onset of flow of a polycrystalline hexagonal columnar phase

Teresa Bauer·Julian Oberdisse·Laurence Ramos
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Abstract

Creep experiments on polycrystalline surfactant hexagonal columnar phases show a power law regime, followed by a drastic fluidization before reaching a final stationary flow. The scaling of the fluidization time with the shear modulus of the sample and stress applied suggests that the onset of flow involves a bulk reorganization of the material. This is confirmed by X-ray scattering under stress coupled to \textit{in situ} rheology experiments, which show a collective reorientation of all crystallites at the onset of flow. The analogy with the fracture of heterogeneous materials is discussed.

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Teresa Bauer, Julian Oberdisse, Laurence Ramos. 2006-12-19. Collective rearrangement at the onset of flow of a polycrystalline hexagonal columnar phase. https://doi.org/10.1103/physrevlett.97.258303

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