Mora Serge, Pomeau Yves
Laboratoire de Mécanique et de Génie Civil, UMR 5508, Université Montpellier 2-CNRS, Place Eugène Bataillon, F-34095 Montpellier Cedex, France.
J Phys Condens Matter. 2015 May 20;27(19):194112. doi: 10.1088/0953-8984/27/19/194112. Epub 2015 Apr 29.
Surface tension tends to minimize the area of interfaces between pieces of matter in different thermodynamic phases, be they in the solid or the liquid state. This can be relevant for the macroscopic shape of very soft solids and lead to a roughening of initially sharp edges. We calculate this effect for a Neo-Hookean elastic solid, with assumptions corresponding to actual experiments, namely the case where an initially sharp edge is rounded by the effect of surface tension felt when the fluid surrounding the soft solid (and so surface tension) is changed at the solid/liquid boundary. We consider two opposite limits where the analysis can be carried to the end, the one of a shallow angle and the one of a very sharp angle. Both cases yield a discontinuity of curvature in the state with surface tension although the initial state had a discontinuous slope.
表面张力倾向于使处于不同热力学相的物质之间的界面面积最小化，无论这些物质处于固态还是液态。这对于非常软的固体的宏观形状可能是相关的，并导致初始尖锐边缘的粗糙化。我们针对一种新胡克弹性固体计算这种效应，其假设对应于实际实验，即当围绕软固体的流体（以及表面张力）在固/液边界处发生变化时，初始尖锐边缘因表面张力的作用而变圆的情况。我们考虑两个可以进行到底的相反极限情况，一个是浅角度情况，另一个是非常尖锐角度情况。尽管初始状态具有不连续的斜率，但在存在表面张力的状态下，这两种情况都会产生曲率的不连续性。
