Univ Paris Diderot, Sorbonne Paris Cité, MSC, UMR CNRS, France.
Phys Rev Lett. 2011 Nov 11;107(20):204503. doi: 10.1103/PhysRevLett.107.204503.
Capillary origami is the wrapping of a usual fluid drop by a planar elastic membrane due to the interplay between capillary and elastic forces. Here, we use a drop of magnetic fluid whose shape is known to strongly depend on an applied magnetic field. We study the quasistatic and dynamical behaviors of such a magnetic capillary origami. We report the observation of an overturning instability that the origami undergoes at a critical magnetic field. This instability is triggered by an interplay between magnetic and gravitational energies in agreement with the theory presented here. Additional effects of elasticity and capillarity on this instability are also discussed.
毛细折纸是指由于毛细力和弹性力的相互作用，平面弹性膜对普通液滴的包裹。在这里，我们使用了一滴磁性液体，其形状已知强烈依赖于施加的磁场。我们研究了这种磁性毛细折纸的准静态和动态行为。我们报告了在一个临界磁场下，折纸经历的翻转不稳定性的观察结果。这种不稳定性是由磁能和重力能之间的相互作用触发的，这与本文提出的理论是一致的。还讨论了弹性和毛细作用对这种不稳定性的附加影响。
