Soft Glassy Materials (SGM) consist in dense amorphous assemblies of colloidal particles of multiple shapes, elasticity, and interactions, which confer upon them solid-like properties at rest. They are ubiquitously encountered in modern engineering, including additive manufacturing, semi-solid flow cells, dip-coating, adhesive locomotion, where they are subjected to complex mechanical histories. Such processes often include a solid-to-liquid transition induced by large enough shear, which results in complex transient phenomena such as non-monotonic stress responses, i.e., stress overshoot, and spatially heterogeneous flows, e.g., shear-banding or brittle failure. In the present article, we propose a pedagogical introduction to a continuum model based on a spatially-resolved fluidity approach that we recently introduced to rationalize shear-induced yielding in SGMs. Our model, which relies upon non-local effects, quantitatively captures salient features associated with such complex flows, including the rate dependence of the stress overshoot, as well as transient shear-banded flows together with nontrivial scaling laws for fluidization times. This approach offers a versatile framework to account for subtle effects, such as avalanche-like phenomena, or the impact of boundary conditions, which we illustrate by including in our model the elasto-hydrodynamic slippage of soft particles compressed against solid surfaces.

中文翻译：

---

剪切下软玻璃材料的连续体建模

软玻璃材料 (SGM) 由具有多种形状、弹性和相互作用的胶体颗粒组成的致密无定形组装体组成，这些胶体颗粒在静止状态下具有类似固体的特性。它们在现代工程中无处不在，包括增材制造、半固态流通池、浸涂、粘合剂运动，它们在这些工程中受​​到复杂的机械历史的影响。这样的过程通常包括由足够大的剪切引起的固-液转变，这会导致复杂的瞬态现象，例如非单调应力响应，即应力过冲和空间异质流动，例如剪切带或脆性破坏。在本文中，我们提出了基于空间分辨流动性方法的连续统模型的教学介绍，我们最近引入了该方法以合理化 SGM 中的剪切诱导屈服。我们的模型依赖于非局部效应，定量地捕捉与这种复杂流动相关的显着特征，包括应力过冲的速率依赖性，以及瞬态剪切带状流动以及流化时间的非平凡比例定律。这种方法提供了一个通用框架来解释微妙的影响，例如雪崩现象或边界条件的影响，我们通过在我们的模型中包含压缩固体表面的软粒子的弹性流体动力学滑移来说明这一点。定量地捕捉与这种复杂流动相关的显着特征，包括应力过冲的速率依赖性，以及瞬态剪切带状流动以及流化时间的非平凡比例定律。这种方法提供了一个通用框架来解释微妙的影响，例如雪崩现象或边界条件的影响，我们通过在我们的模型中包含压缩固体表面的软粒子的弹性流体动力学滑移来说明这一点。定量地捕捉与这种复杂流动相关的显着特征，包括应力过冲的速率依赖性，以及瞬态剪切带状流动以及流化时间的非平凡比例定律。这种方法提供了一个通用框架来解释微妙的影响，例如雪崩现象或边界条件的影响，我们通过在我们的模型中包含压缩固体表面的软粒子的弹性流体动力学滑移来说明这一点。