Noncontact rotation, levitation, and acceleration of flowing liquid metal wires

Abstract

This paper reports the noncontact manipulation of free-falling cylindrical streams of liquid metals into unique shapes, such as levitated loops and squares. Such cylindrical streams form in aqueous media by electrochemically lowering the interfacial tension. The electrochemical reactions require an electrical current that flows through the streams, making them susceptible to the Lorentz force. Consequently, varying the position and shape of a magnetic field relative to the stream controls these forces. Moreover, the movement of the metal stream relative to the magnetic field induces significant forces arising from Lenz’s law that cause the manipulated streams to levitate in unique shapes. The ability to control streams of liquid metals in a noncontact manner will enable strategies for shaping electronically conductive fluids for advanced manufacturing and dynamic electronic structures.

On-demand liquid microlens arrays by non-contact relocation of inhomogeneous fluids in acoustic fields

“…Wavefield-based contact-free approaches offer a unique route for fluid manipulation that minimizes the disturbance to the target object and significantly improves accuracy. 30 They also contribute to the miniaturization of devices because complex and bulky facilities can be avoided. Acoustic methods have been proven as a promising technology for handling microparticles in a non-invasive and flexible manner.…”

Reciprocating Oscillation of a Floating Ferrofluid Marble Triggered by Magnetic Fields

“…After inducing the surface deformation magnetically, the LMs can achieve artificially controlled motion, regardless of whether they are magnetic . In summary, the introduction of the magnetic field significantly broadens the application range of LMs and is a potential contactless manipulation method. − …”

Interdigitating Elastic Fibers with a Liquid Metal Core toward Ultrastretchable and Soft Capacitive Sensors: From 1D Fibers to 2D Electronics

“…6,7 They can also be incorporated into the elastic substrates to fabricate soft and stretchable electronics; however, they can make the substrates retain elastic properties due to the fluidic nature of electrodes. 8,9 Liquid metal can form a thin oxide layer (∼3 nm) in the air; 10,11 hence, it can be adhered to various substrates and patterned into desired shapes via unconventional methods such as injection, 12,13 vacuum filling, 14,15 direct writing, 16,17 forced wetting, 18,19 and elastic molding. 20,21 Another method to fabricate stretchable devices is rendering the liquid metal into particles and utilizing them as soft conductive fillers in the polymeric matrix.…”

“…Gallium-based liquid metals as electrodes are appealing to address this issue. , They can also be incorporated into the elastic substrates to fabricate soft and stretchable electronics; however, they can make the substrates retain elastic properties due to the fluidic nature of electrodes. , Liquid metal can form a thin oxide layer (∼3 nm) in the air; , hence, it can be adhered to various substrates and patterned into desired shapes via unconventional methods such as injection, , vacuum filling, , direct writing, , forced wetting, , and elastic molding. , Another method to fabricate stretchable devices is rendering the liquid metal into particles and utilizing them as soft conductive fillers in the polymeric matrix. Once the liquid metal particles are dispersed in the polymeric matrix, they can rupture the oxide layer and subsequently restore the electrical conductivity by mechanical sintering-induced percolation. , In addition, an electrical pathway can also be formed by utilizing biphasic composites (Ag-In-Ga) and a hydrogen-doping induced conductive and deformable oxide skin on the liquid particles …”