In the present paper, we experimentally investigate the impingements of a liquid metal drop on the electrolyte solution pool. The experimental setup consists of an electromagnet, liquid metal droplet generating system, argon-protecting vessel for drop impact, and high-speed imaging system. The setup can capture the dynamic phenomena of droplet impact upon and below the free surface of the electrolyte pool under different conditions (with or without a magnetic field, different droplet diameters, and impact velocities). Upon the surface of pool, we observed three typical outcomes after drop impact on the pool, namely, thin jet with second droplet, prompt splash with a thick jet, and thick jet with second droplet, among which the prompt splash with the thick jet is only observed in the presence of horizontal magnetic field. The horizontal magnetic field can inhibit the height of central jet and the occurrence of second droplet, and such effect becomes stronger when the strength of magnetic field increases. On the other hand, several phenomena were observed below the surface of pool, i.e. ellipsoid vibration, flat vibration, bowl deformation, the collapse and second bowl deformation with or without magnetic field. The horizontal magnetic field, which promotes a "bulge" of the flat vibration and bowl deformation, affects the critical We of the occurrence of bowl deformation, the collapse and second bowl deformation. In addition, we found the relationships between the motion of liquid metal drop upon and below the surface of pool. Experimental results reveal that the complex phenomena can be observed when the liquid metal drop impacts on the electrolyte solution pool under the influence of an external magnetic field, it is worthy of further investigations both by detailed experiments and numerical simulations.
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