Liquid metal

About: Liquid metal is a research topic. Over the lifetime, 6947 publications have been published within this topic receiving 77785 citations. The topic is also known as: liquid alloy & liquid metal alloy.

Liquid-Metal Microdroplets Formed Dynamically with Electrical Control of Size and Rate

Abstract: Liquid metal co-injected with electrolyte through a microfluidic flow-focusing orifice forms droplets with diameters and production frequencies controlled in real time by voltage. Applying voltage to the liquid metal controls the interfacial tension via a combination of electrochemistry and electrocapillarity. This simple and effective method can instantaneously tune the size of the microdroplets, which has applications in composites, catalysts, and microsystems.

Generation of Droplets in Slag-Metal Emulsions through Top Gas Blowing

Abstract: The behavior of metal droplets in a slag-metal-gas emulsion through impinging gas blowing was investigated experimentally using a cast iron-slag-nitrogen gas system at high temperatures. A mathematical model of the emulsification process for determining the generation rate, size distribution, and residence time of metal droplets has been developed and successfully validated using experimental data. From the present work, it was found that the generation rate and size distribution of metal droplets is strongly influenced by the ratio of the inertial force of blown gas to the surface tension and buoyancy forces of the liquid metal. A new dimensionless number, i.e. blowing number, which represents the ratio of inertial to surface tension and buoyancy forces and also the departure of the system from its stable condition defined by the Kelvin-Helmholtz criterion, is proposed. A functional relationship of generation rate and size distribution of metal droplets with the blowing number is proposed.

Electronic and structural transitions in dense liquid sodium

Abstract: It has recently been shown that, when high pressures are applied, crystals of lithium and sodium undergo a sequence of phase transitions — including (for sodium) a striking and as yet unexplained pressure-induced drop in the melting temperature. Jean-Yves Raty et al. have now identified the cause of this unusual melting behaviour: it emerges because liquid sodium undergoes a series of transitions similar to those seen in the solid state, but at much lower pressures. Intriguingly, one of these transitions is driven by the opening of a 'pseudogap' in the electronic density of states, the first time such an effect has been seen in a liquid metal. When high pressures are applied, crystals of lithium and sodium undergo a sequence of phase transitions, including a striking pressure-induced drop in the melting temperature. The cause of the unusual melting behaviour has now been identified: it emerges because liquid sodium undergoes a series of transitions similar to those seen in the solid state, but at much lower pressures. One of these transitions is driven by the opening of a 'pseudogap' in the electronic density of states. At ambient conditions, the light alkali metals are free-electron-like crystals with a highly symmetric structure. However, they were found recently to exhibit unexpected complexity under pressure1,2,3,4,5,6. It was predicted from theory1,2—and later confirmed by experiment3,4,5—that lithium and sodium undergo a sequence of symmetry-breaking transitions, driven by a Peierls mechanism, at high pressures. Measurements of the sodium melting curve6 have subsequently revealed an unprecedented (and still unexplained) pressure-induced drop in melting temperature from 1,000 K at 30 GPa down to room temperature at 120 GPa. Here we report results from ab initio calculations that explain the unusual melting behaviour in dense sodium. We show that molten sodium undergoes a series of pressure-induced structural and electronic transitions, analogous to those observed in solid sodium but commencing at much lower pressure in the presence of liquid disorder. As pressure is increased, liquid sodium initially evolves by assuming a more compact local structure. However, a transition to a lower-coordinated liquid takes place at a pressure of around 65 GPa, accompanied by a threefold drop in electrical conductivity. This transition is driven by the opening of a pseudogap, at the Fermi level, in the electronic density of states—an effect that has not hitherto been observed in a liquid metal. The lower-coordinated liquid emerges at high temperatures and above the stability region of a close-packed free-electron-like metal. We predict that similar exotic behaviour is possible in other materials as well.

Thermophysical properties of liquid copper and aluminum

Abstract: The electrical resistivity and equation of state of liquid copper and aluminum have been measured to temperatures of 4500 and 4000 K, respectively, using the isobaric expansion apparatus. The specific heats for the liquid are in good agreement with extrapolation of the 1973 Hultgren tables. The electrical resistivities are presented both with and without correction for thermal expansion. Both resistivity and thermal expansion results for aluminum are compared with the predictions of pseudopotential calculations. The specific volumes observed for both metals are less than those reported in the literature, apparently because of axial hydrodynamic displacement. In addition, sudden rapid acceleration in sample growth rate with a corresponding rapid rise in resistivity were observed.