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Liquid metals are a class of materials with a millennia‐long history, albeit until 200 years ago, mostly centered on mercury‐based applications. The knowledge of mercury's toxicity and the discovery of it's bioaccumulation and biomagnification in the late 20th century resulted in phasing out mercury for copious application. Lead‐based, bismuth‐based, and sodium‐based technology has partially replaced mercury, but due to toxicity or reactivity issues, replacements for lead and sodium are sought. The discovery of indium and, especially, gallium has allowed for the third generation of alloys with a melting point close to room temperature. This review gives a comprehensive overview of the technological developments of fusible and liquid metals, i. e. metals and alloys with melting points below ca. 250 °C, from the early days to current research and industrial application. Special emphasis is focused on important steppingstones and recent developments of gallium‐based alloys as well as how they could be used for future applications. [ABSTRACT FROM AUTHOR]

The synthesis conditions for the gadolinium manganite doped with barium (x = 0.1) are determined. The sequence and typical features of phase formation during the synthesis of Gd0.9Ba0.1MnO3 are determined. It is revealed that the β→γ-BaCO3 phase transformation at T = 960 °C leads to an increase in the reactivity of the initial reagents. At this stage, the Gd0.9Ba0.1MnO3 formation centers begin to grow. Intermediate grinding is necessary to homogenize the phase; additional annealing at T = 1250 °C is applied to stabilize the phase. Substitution of Gd for Ba changes the microstructure of the manganite and leads to suppression of grain growth. Modification of the GdMnO3 manganite with barium leads to partial removal of the Jahn-Teller distortions, and as a consequence to a decrease in temperature of the phase transition O'→O. The addition of barium does not affect noticeably the magnetic behavior of the initial manganite but decreases the magnetic moment and stimulates ferromagnetic correlations in its antiferromagnetic manganese subsystem. [ABSTRACT FROM AUTHOR]

We report results of magnetic studies of glass-forming alloys with nominal composition of AlGdTM (where TM = Cu, Ni, Co, Fe, Mn, Cr, Ti, Zr, Mo, Ta) synthesized by arc-melting. X-ray diffraction analysis and vibrating sample magnetometry were applied to characterize the prepared samples. All the alloys exhibit antiferromagnetic ordering at low temperatures. In some compositions, we observed metamagnetic transitions in external magnetic fields up to 3 T. Analysis of the paramagnetic susceptibility of the considered Al-Gd-TM systems has revealed non-magnetic behavior of the transition metals. We found that the magnetic properties of the studied samples can be described satisfactorily using only the Gd trivalent ions. But in some cases the magnetic moments of gadolinium are slightly larger than the theoretical values, probably, because of an additional contribution of the 5 d electrons. The obtained results are discussed in framework of the assumptions of the strong s- p- d hybridization and frustrated magnetic states of gadolinium. We argue that the hybridization might be one of the main factors improving the glass-forming ability in these ternary alloys. [ABSTRACT FROM AUTHOR]

One of the intriguing recent results in the field of high-entropy alloys is the discovery of single-phase equiatomic multi-component Laves intermetallics. However, there is no clear understanding that a combination of chemical elements will form such high-entropy compounds. Here we contribute to understanding this issue by modifying the composition of duodenary TiZrHfNbVCrMoMnFeCoNiAl (12x) alloy in which we recently reported the fabrication of hexagonal C14 Laves phase. We consider three alloys based on 12x: 7x = 12x-VCrMoMnFe, 12x + Sc, 12x + Be and observe that all of them crystalize with the formation of C14 Laves phase as a dominant structure. We report that 12x + Be alloy reveals a single-phase C14 structure with a very high concentration of structural defects and ultra-fine dendritic microstructure with an almost homogenous distribution of the constituted elements over the alloy matrix. The analysis of electrical and magnetic properties reveals that the Laves phases are Curie-Weiss paramagnets, which demonstrate metallic conduction; 7x and 12x alloys also reveal a pronounced Kondo-like anomaly. Analysis of experimental data as well as ab initio calculations suggest that chemical complexity and compositional disorder cause strong s-d band scattering and thus the rather high density of d-states in the conduction band. [ABSTRACT FROM AUTHOR]

The synthesis conditions for the gadolinium manganite doped with barium (x = 0.1) are determined. The sequence and typical features of phase formation during the synthesis of Gd0.9Ba0.1MnO3 are determined. It is revealed that the β→γ-BaCO3 phase transformation at T = 960 °C leads to an increase in the reactivity of the initial reagents. At this stage, the Gd0.9Ba0.1MnO3 formation centers begin to grow. Intermediate grinding is necessary to homogenize the phase; additional annealing at T = 1250 °C is applied to stabilize the phase. Substitution of Gd for Ba changes the microstructure of the manganite and leads to suppression of grain growth. Modification of the GdMnO3 manganite with barium leads to partial removal of the Jahn-Teller distortions, and as a consequence to a decrease in temperature of the phase transition O'→O. The addition of barium does not affect noticeably the magnetic behavior of the initial manganite but decreases the magnetic moment and stimulates ferromagnetic correlations in its antiferromagnetic manganese subsystem. [ABSTRACT FROM AUTHOR]

The polycrystalline ErMnO 3 with a hexagonal structure, synthesized by ceramic technology, and its derivative samples obtained by mechanical activation were studied by high-temperature X-ray diffraction analysis and magnetometry. It has been found that the phase transition from the polar P63 cm structural modification to the centrosymmetric P63/ mmc proceeds in ErMnO 3 in two stages (at 650 °С and 1150 °С). Grain growth kinetics in mechanically activated ErMnO 3 samples was studied; the activation energy values were determined. The magnetic phase transitions, corresponding to the antiferromagnetic ordering, were detected for all samples. The Neel point was found to decrease from 75 to 62 K with decreasing grain size from ∼300 to ∼50 nm. It was found that the electronic structure of the materials does not change noticeably upon mechanical activation. The observed lowering of the Neel temperatures in the mechanically activated samples was accounted for by multiple lattice distortions. [ABSTRACT FROM AUTHOR]

Manganites of rare earth elements are currently promising materials for electronics, catalysis, current sources and other applications. Their widespread demand is caused by a variety of structural and magnetic effects connected with substitutions in the sublattices of rare earth element and manganese. Substitutions of rare earth element by Sr, Ca, or Ba in manganites are known to impact the Jahn-Teller (JT) transition temperature as well as the concentration of Mn3+ and Mn4+ ions, which influences the efficiency of double exchange in magnetic orderings. In this work, solid solution Sm1-xSrxMnO3 with low concentrations of the substituting element x = 0; 0.15; 0.25 has been studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermal analysis, and magnetometry. Samarium manganites have a perovskite-like orthorhombic structure (Pbnm space group). It has been shown that the Sm-by-Sr substitution leads to a gradual increase in the valence of manganese from 3 + to intermediate value 3.67+. This is accompanied by an increase Néel temperature in (TN) from 56 K at x = 0 to 90 K at x = 0.25, in the paramagnetic Curie temperature (Θ) from − 30.3 K at x = 0 to 119.9 K at x = 0.25, as well as in the value of the saturation magnetic moment (µS) from 0.27 µB at x = 0 to 3.49 µB at x = 0.25. In addition, such substitution leads to a decrease in the temperature of the JT structural transition from 996 ºC at x = 0.0 to 252 ºC at x = 0.25. The relationship between the magnetic properties and the crystal structure of samarium manganites is discussed. [ABSTRACT FROM AUTHOR]