The significant effect of an external dc magnetic field on the splashing behavior of ethanol drops impacting on the unstructured (flat) surface of soft magnetoactive elastomers (MAEs) is reported. ...The Weber number corresponding to the transition between the deposition and the splashing regime is reduced by ≈20% in a moderate magnetic field of ≈300 mT. Alongside this effect, a two‐fold increase of the initial deceleration of the ejection sheet is observed for the softest sample. The main underlying mechanism for the observed phenomena is believed to be the magnetic‐field‐induced stiffening of the MAEs. Further possible mechanisms are magnetically induced changes in the surface roughness and magnetic‐field‐induced plasticity (magnetic shape memory effect). The potential application areas are magnetically regulable wetting and magneto‐responsive surfaces for controlling the drop splashing.
The magnetic‐field‐induced functionality of magnetoactive‐elastomer surfaces is used for affecting the process of drop splashing. The application of a moderate magnetic field allows one to switch between the regimes of drop deposition and splashing. This finding opens up unprecedented possibilities for developing magnetically sensitive coatings for splash control and may contribute to the understanding of splashing mechanisms by new experimental methodology.
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