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In this review paper, using the example of AM–Pb and AM–Bi melts (AM is an alkali metal), modern ideas on the nature of chemical short-range order in liquid metal systems with partial ionic bonding are briefly presented. Generalization and analysis of the experimental data obtained by the authors on the volumetric properties and mutual diffusion in liquid alloys of alkali metals with lead and bismuth have been carried out. The behavior of these properties is shown to generally agree with existing simple models that assume the presence of ionic complexes in melts, which gradually dissociate with increasing temperature. At the same time, the need to refine the structure of polyanionic complexes in liquid AM–Bi systems is confirmed. [ABSTRACT FROM AUTHOR]

The volumetric properties of liquid indium-lead alloys containing 20 and 33 at. % Pb have been measured using gamma-ray attenuation technique at temperatures from the liquidus line to 880 K. The density changes of these alloys during solid–liquid phase transition have been calculated. The obtained experimental values of the molar volume and the volumetric thermal expansion coefficient of melts and the results of calculations according to the laws for an ideal solution and data of other authors have been compared. [ABSTRACT FROM AUTHOR]

The density of liquid mixtures of lithium and potassium fluorides with a content of 51.2 and 71.1 mol % LiF was measured using gamma-ray attenuation technique in the temperature range from liquidus to 1000–1190 K. For a mixture of near-eutectic composition (51.2 mol % LiF), the relative density change during the solid–liquid phase transition and the density in the solid state near the melting point were directly determined for the first time. The concentration dependences of the molar volume and volumetric coefficient of thermal expansion for the LiF–KF liquid system were plotted on the basis of the experimental and literature data. The obtained dependences were found to be close to the concentration dependences of the corresponding volumetric properties for ideal solutions. [ABSTRACT FROM AUTHOR]

Using the method of differential scanning calorimetry, the heat capacity of Mg-Ca alloys containing 10.50, 33.34, and 73.00 at. % Ca, being promising for various practical applications (biocompatible and biodegradable alloys, ultralight construction materials, anode materials, hydrogen absorbent materials, etc.) has been studied experimentally. New reliable experimental results on the heat capacity in the temperature range of 190–576÷692 K of the solid state have been obtained. The estimated errors of the received data were 2–3 %. The reference table for temperature dependences of heat capacity of Mg-Ca alloys has been compiled. It has been established, that over a wide temperature range the heat capacity of solid magnesium-calcium alloys can be estimated with high accuracy using the Neumann–Kopp rule. [ABSTRACT FROM AUTHOR]

The enthalpy and heat capacity of solid and liquid Mg2Ca intermetallic alloy were measured by massive high-temperature isothermal drop calorimeter over the temperature range of 298.15–1177 K. The estimated errors in the data on enthalpy and heat capacity were 0.2 % and 2 %, respectively. The fusion enthalpy of the Mg2Ca intermetallic alloy was determined to be 483 ± 3 J/g. The heat capacity of the Mg2Ca melt was shown to be constant in the range of 993.2–1177 K. A comparison of the obtained results with literature data has been carried out. [ABSTRACT FROM AUTHOR]

The density of liquid lithium fluoride and an eutectic mixture of lithium fluoride and sodium fluoride (with a content of 39 mol % NaF) was measured by the gamma-ray attenuation method in the temperature range from liquidus to ∼1280 K. The obtained results were compared with the available literature data. The study of liquid eutectic LiF–NaF was carried out in a much wider temperature range compared to other authors, and the obtained values of the volumetric coefficient of thermal expansion turned out to be the most reliable. [ABSTRACT FROM AUTHOR]

A comprehensive study of the thermophysical properties of an ultralight eutectic Mg-Li alloy (with a lithium content of 23 at. %), promising for use in the aerospace industry has been carried out. New reliable experimental data have been obtained for thermal conductivity, thermal diffusivity, specific heat capacity, density, linear thermal expansion coefficient, and relative elongation of the alloy in the temperature range of 300–781 K. The obtained results have been compared with well—known literature data on thermal conductivity and thermal expansion for Mg-Li system alloys. Approximation equations and a table of reference data of the studied properties are presented. The relative density change during melting of eutectic has been determined. [ABSTRACT FROM AUTHOR]

The transfer properties of a congruently melting Mg-Li alloy with a lithium content of 30 at. %, considered as a promising ultralight structural material for the aerospace industry, have been studied experimentally. New experimental data on thermal diffusivity (a) and thermal conductivity (λ) have been obtained in the temperature range of 293–777 K with estimated errors of 2–4 % and 3–5 %, respectively. The results have been compared with the known literature data on thermal conductivity of Mg-Li system alloys. A table of recommended temperature dependences for a and λ of the studied composition has been developed. [ABSTRACT FROM AUTHOR]

The solubility of heavy alkali metals in liquid lithium was investigated at temperatures from the melting point of Li to ∼1200 K by the method of gamma-raying of liquid samples by a narrow beam of gamma radiation. Even at high temperatures, the solubility of K, Rb, and Cs in liquid lithium has been found to be very insignificant. The potassium content in the lithium-rich phase is 0.2 at. % at 850 K and 3.4 at. % at 1212 K. The solubility of rubidium in liquid lithium, within the measurement error, is zero at temperatures from 453 K (melting point of Li) to 800 K and reaches only 0.5 at. % at 1172 K. Cesium is practically insoluble in liquid lithium up to a temperature of 1150 K. [ABSTRACT FROM AUTHOR]

Using the laser flash method and the drop method, the thermal conductivity and the enthalpy increment of the eutectic K-Pb alloy (with a Pb content of 90.7 at.%) were measured in the temperature range from the liquidus point up to 1077–1175 K. The specific heat capacity and thermal diffusivity of the alloy were calculated. Approximation equations for the studied properties were obtained, and a table of reference data was developed. It was shown that the thermal conductivity of the liquid eutectic is less than that of pure lead and increases with temperature. [ABSTRACT FROM AUTHOR]

Using the laser flash method the thermal conductivity of the Rb-Bi liquid alloy with a bismuth content of 27 at. % was measured in the temperature range from the liquidus point to 1173 K. Approximation equations for thermal conductivity and thermal diffusivity have been obtained, and a table of reference data has been developed. An analysis of the measurement results confirms the existing assumption of the presence of intermetallic complexes with a partially ionic nature of the interatomic interaction in Rb-Bi melts. [ABSTRACT FROM AUTHOR]

The density and thermal expansion of the solid and liquid Inconel 718 alloy are measured by the dilatometer method and gamma-ray attenuation technique over the temperature range 293.15–1730 K. The density change during the solid-liquid phase transition is directly measured. A comparison of the obtained results with literature data is carried out. [ABSTRACT FROM AUTHOR]

The thermal conductivity λ and the thermal diffusivity a of liquid rubidium were measured by the laser flash method in the temperature interval from the melting point up to 873 K. The measurement error was 4-6%. The data of this paper were compared with the results of other authors. Approximation equations and the table of reference values for the temperature dependence of λ and a have been obtained. The dependence of the Lorentz number on temperature has been calculated. [ABSTRACT FROM AUTHOR]

The density and the thermal expansion of liquid lithium-lead alloys with Pb content of 83.0 and 84.3 at. % was measured using gamma-ray attenuation technique over the temperature range from liquidus to 1000 K. The density change during solid-liquid phase transition was directly measured for the first time for Li15.7Pb84.3 alloy. A comparison of the obtained results with literature data has been carried out. [ABSTRACT FROM AUTHOR]