Andriy Yakymovych - Academia.edu (original) (raw)

Papers by Andriy Yakymovych

Structure of liquid Sb-Sn alloys were studied by means of viscosity measurements and X-ray diffra... more Structure of liquid Sb-Sn alloys were studied by means of viscosity measurements and X-ray diffraction. Structural factors and pair correlation functions were analysed and interpreted using the random atomic distribution model. The features of temperature dependence of the viscosity coefficient were analysed taking into account X-ray diffraction patterns. The results allow us to conclude that Sb atoms substitute for Sn atoms, forming a typical atomic solution, which reveals chemical and topological short-range order. Moreover, certain atoms form Sband Sn-based SbnSnm associates and self-associates.

Journal of Physical Studies, 2008

The viscosity of Al1−xNix (x = 0.025; 0.05 and 0.075) molten alloys has been studied by means of ... more The viscosity of Al1−xNix (x = 0.025; 0.05 and 0.075) molten alloys has been studied by means of oscillating crucible method. The temperature dependence of dynamical viscosity coefficient is obtained and activation energy is estimated from them. The analysis of concentration dependence of viscosity coefficient reveals its deviation from linear dependence. Significant increase of viscosity coefficient for liquid aluminum upon the addition of Ni-atoms is caused by cluster formation and increase of their size.

High Temperatures-High Pressures, 2020

In this study, some structure-sensitive thermophysical properties, namely, thermal conductivity, ... more In this study, some structure-sensitive thermophysical properties, namely, thermal conductivity, thermoelectric power, density and surface tension of liquid AlCu4TiMg alloy, as one of the most promising cast alloys to fabricate components for cars, aircraft and other complex engineering products, were investigated. Thermoelectric power was measured in a wide temperature range by the four-point contact method. Thermal conductivity was investigated by the steady-state concentric cylinder method. The oscillating drop technique combined with electromagnetic levitation was used for density and surface tension studies. The results obtained are compared with experimental and calculated data from literature for pure aluminum.

Applied Nanoscience, 2020

The effect of bimetallic monodisperse CoPd nanoparticles on the microstructure and the shear stre... more The effect of bimetallic monodisperse CoPd nanoparticles on the microstructure and the shear strength of the Cu/ SAC305/ Cu solder joint was investigated. The nanocomposite Sn-3.0Ag-0.5Cu (SAC305) solders with 0.1, 0.3, 0.5, and 1.0 wt% nanoCoPd were prepared through a paste mixing method. The employed bimetallic nanoparticles were produced via a modified oleylamine method. The microstructural analysis of as-solidified Cu/solder/Cu joints was performed by scanning electron microscopy. The results showed that initial additions of CoPd nanoparticles into the SAC305 solder promoted the growth of the interfacial planar-type Cu 3 Sn IMC layer; while the average thickness of the interfacial scallop-type Cu 6 Sn 5 IMC layer slightly decreased. Further additions of the nanosized CoPd admixtures to the SAC305 solder paste lead to a significant increase of the average thickness of the Cu 6 Sn 5 intermetallic compound layer up to 40%. The shear strength measurements were performed to investigate a relationship between the microstructure and mechanical properties of the investigated solder joints. The results indicated a decrease in the shear strength of the SAC305 solder joint by addition of 0.1 wt% CoPd NPs, while a difference in absolute values between solder joints with 0.3, 0.5, and 1.0 wt% nanoCoPd was practically insignificant.

Chemistry of Metals and Alloys, 2008

The enthalpy of mixing of binary In-Bi melts was measured by means of a calorimetric method at T ... more The enthalpy of mixing of binary In-Bi melts was measured by means of a calorimetric method at T = 1023, 875, 483 K. Its concentration dependence reveals a flat minimum in the region between the intermetallic phases InBi and In 2 Bi. The shape of the curve of the integral enthalpy of mixing for liquid In-Bi alloys is in agreement with the assumption of a competition between InBi-and In 2 Bi-like chemical ordering before solidification. Enthalpy of mixing / In-Bi molten alloys / Intermetallic phase / Associate

RSC Advances, 2018

Difference in the enthalpy effect by replacing micro- by nano-sized particles in drop calorimetry.

Journal of Molecular Liquids, 2018

The impact of minor additions of Ni nanoparticles on the dynamic viscosity of the liquid Sn-3.0Ag... more The impact of minor additions of Ni nanoparticles on the dynamic viscosity of the liquid Sn-3.0Ag-0.5Cu alloy (SAC305; in wt.%) is examined. The nanocomposite samples were prepared from commercial SAC305 powder and Ni nanopowder by cold pressing. The dynamic viscosity of the (Sn96.5Ag3.0Cu0.5)100-xNix alloys measured during heating and cooling exhibited a hysteresis in a temperature range up to 100 K above the melting temperature. This is supposed to be related to the structural transformations caused by dissolution of Ni nanoparticles in the liquid Sn-based matrix upon heating. The experimental values of the viscosity of the (Sn96.5Ag3.0Cu0.5)100-xNix alloys are in a good agreement with calculated data using thermodynamic approaches.

Metallurgical and Materials Transactions A, 2018

The density of the liquid equiatomic high-entropy alloys, namely, AlCoCrCuFeNi, AlCoCu-FeNi, and ... more The density of the liquid equiatomic high-entropy alloys, namely, AlCoCrCuFeNi, AlCoCu-FeNi, and CrCoCuFeNi, as well as quaternary alloys AlCoCuFe and AlCoCrNi was determined over a wide temperature range. The measurements were performed by a non-contact technique combining electromagnetic levitation and optical dilatometry. The temperature and composition dependencies of the density were analyzed and the molar excess volumes were calculated. The integral enthalpy of mixing of multi-component alloys was predicted using extended Kohler's model, while Miedema's model was used for binary subsystem alloys. It has been found that a negative excess volume of the investigated Al-containing liquid alloys correlates with a negative enthalpy of mixing. In contrast, a positive excess volume and an endothermic reaction have been estimated for the liquid CoCrCuFeNi alloy. The change of the excess volume in the Al-containing liquid alloys is affected by two basic effects, namely, compression of the Al matrix and formation of compounds in the melt.

Materials Chemistry and Physics, 2016

SnAg -Cu (SAC) alloys are commonly recognized as lead-free solders employed in the electronics in... more SnAg -Cu (SAC) alloys are commonly recognized as lead-free solders employed in the electronics industry. However, some disadvantages in mechanical properties and their higher melting temperatures compared to Pb-Sn solders prompt new research relating to reinforcement of existing SAC solders. One of the ways to reinforce these solder materials is the formation of composites with nanoparticles as filler materials. Accordingly, this study presents structural features of nanocomposite (Sn-3.0Ag-0.5Cu) 100-x (nanoCo) x solders with up to 0.8 wt.% nano Co. The effect of nano-sized Co particles was investigated by means of differential thermal analysis (DTA), X-ray diffraction (XRD) in both liquid and solid states, and scanning electron microscopy (SEM). The experimental data of DTA are compared with available literature data for bulk Sn-3.0Ag-0.5Cu alloy to check the capability of minor nanoinclusions to decrease the melting temperature of the SAC solder. The combination of structural data in liquid and solid states provides important information about the structural transformations of liquid Sn-3.0Ag-0.5Cu alloys caused by minor Co additions and the phase formation during crystallization. Furthermore, scanning electron microscopy has shown the mutual substitution of Co and Cu atoms in the Cu 6 Sn 5 and CoSn 3 phases, respectively.

Journal of Mining and Metallurgy, Section B: Metallurgy, 2017

In this study, some structure-sensitive thermophysical properties, namely, electrical conductivit... more In this study, some structure-sensitive thermophysical properties, namely, electrical conductivity, thermal conductivity and thermoelectric power of liquid binary alloys Al33.3Mg66.7, Mg47.6Zn52.4 and Mg33.3Zn66.7 (all in wt.%), as the most promising cast alloys to fabricate components for cars, aircraft and other complex engineering products, were investigated. The electrical conductivity and thermoelectric power were measured in a wide temperature range by the four-point contact method. The thermal conductivity was measured by the steady-state concentric cylinder method. The obtained results are compared with literature experimental and calculated data.

Journal of Electronic Materials, 2016

Although considerable research has been dedicated to the synthesis and characterization of lead-f... more Although considerable research has been dedicated to the synthesis and characterization of lead-free nanoparticle solder alloys, only very little has been reported on the reliability of the respective joints. In fact, the merit of nanoparticle solders with depressed melting temperatures close to the Sn-Pb eutectic temperature has always been challenged when compared with conventional solder joints, especially in terms of inferior solderability due to the oxide shell commonly present on the nanoparticles, as well as due to compatibility problems with common fluxing agents. Correspondingly, in the current study, SnAg -Cu (SAC) nanoparticle alloys were combined with a proper fluxing vehicle to produce prototype nanosolder pastes. The reliability of the solder joints was successively investigated by means of electron microscopy and mechanical tests. As a result, the optimized condition for employing nanoparticles as a competent nanopaste and a novel procedure for surface treatment of the SAC nanoparticles to diminish the oxide shell prior to soldering are being proposed.

The Journal of Physical Chemistry C, 2016

Heat effects for the addition of Co in bulk and nanosized forms into the liquid Sn-3.8Ag-0.7Cu al... more Heat effects for the addition of Co in bulk and nanosized forms into the liquid Sn-3.8Ag-0.7Cu alloy were studied using drop calorimetry at four temperatures between 673 and 1173 K. Significant differences in the heat effects between nano and bulk Co additions were observed. The considerably more exothermic values of the measured enthalpy for nano Co additions are connected with the loss of the surface enthalpy of the nanoparticles due to the elimination of the surface of the nanoparticles upon their dissolution in the liquid alloy. This effect is shown to be independent of the calorimeter temperature (it depends only on the dropping temperature through the temperature dependence of the surface energy of the nanoparticles). Integral and partial enthalpies of mixing for Co in the liquid SAC-alloy were evaluated from the experimental data.

Physics and Chemistry of Liquids, 2015

ABSTRACT The Co–Sn system is an important subsystem for Sn-based anode materials of lithium-ion b... more ABSTRACT The Co–Sn system is an important subsystem for Sn-based anode materials of lithium-ion batteries. Experimental results on the physical–chemical properties of this system in the liquid state, however, are rather sparse. In this work, the atomic structure and structure-sensitive thermophysical properties (viscosity, electrical resistivity, and thermoelectric power) of liquid Co–Sn alloys were investigated in a wide temperature range with special attention to the melting-solidification region. The obtained experimental results were combined with differential thermal analysis (DTA) data in order to verify the liquidus curve in the Sn-rich part of the Co–Sn phase diagram.

Journal of Alloys and Compounds, 2014

An analysis of the structure features of liquid Co-Sn alloys has been performed by means of X-ray... more An analysis of the structure features of liquid Co-Sn alloys has been performed by means of X-ray diffraction method, viscosity coefficient analysis and computer simulation method. The X-ray diffraction investigations were carried out over a wide concentration range at the temperature 1473 K. It was found that the structure of these alloys can be described in the frame of independent X-ray scattering model. The viscosity coefficient was calculated by an excess entropy scaling and compared with experimental data.

Inorganic Materials, 2010

The viscosity of Sb-Sn melts containing 0, 5, 10, and 20 at % antimony has been measured as a fun... more The viscosity of Sb-Sn melts containing 0, 5, 10, and 20 at % antimony has been measured as a function of temperature by the oscillating cylinder method. The composition and temperature dependences of the viscosity coefficient deviate from classical theory predictions. The anomalous behavior is interpreted in terms of melt structure and changes in short range order. Structural changes in the Sb-Sn melts are assumed to lead to an anomalous increase in viscosity coefficient.

Monatshefte für Chemie - Chemical Monthly, 2014

The partial and integral molar enthalpies of mixing of liquid Co-Li-Sn alloys were determined usi... more The partial and integral molar enthalpies of mixing of liquid Co-Li-Sn alloys were determined using drop calorimetry. The investigations were performed along six sections by the addition of lithium to mixtures with the compositions x Co /x Sn & 2:98, x Co /x Sn & 1:9, and x Co /x Sn & 3:17 as well as by the addition of cobalt to mixtures with the compositions x Li /x Sn & 3:17, x Li /x Sn & 1:2, and x Li /x Sn & 1:1 at a temperature of 1,173 K. The Co-Li-Sn system shows exothermic behavior of the integral molar enthalpy of mixing in the investigated concentration range. The integral molar enthalpy of mixing of liquid Co-Li system was calculated by Miedema's model to fit our measured ternary data using an extended Redlich-Kister-Muggianu model for substitutional solutions.

The Journal of Chemical Thermodynamics, 2013

Integral molar enthalpies of mixing were determined by drop calorimetry for Cu-Li-Sn at 1073 K al... more Integral molar enthalpies of mixing were determined by drop calorimetry for Cu-Li-Sn at 1073 K along five sections x Cu /x Sn % 1:1, x Cu /x Sn % 2:3, x Cu /x Sn % 1:4, x Li /x Sn % 1:1, and x Li /x Sn % 1:4. The integral and partial molar mixing enthalpies of Cu-Li and Li-Sn were measured at the same temperature, for Li-Sn in addition at 773 K. All binary data could be described by Redlich-Kister-polynomials. Cu-Li shows an endothermic mixing effect with a maximum in the integral molar mixing enthalpy of 5300JAˊmolAˋ1atxCu=0.5,Li−Snanexothermicminimumof5300 J Á mol À1 at x Cu = 0.5, Li-Sn an exothermic minimum of 5300JAˊmolAˋ1atxCu=0.5,Li−Snanexothermicminimumof À37,000 J Á mol À1 at x Sn $ 0.2. For Li-Sn no significant temperature dependence between 773 K and 1073 K could be deduced. Our measured ternary data were fitted on the basis of an extended Redlich-Kister-Muggianu model for substitutional solutions. Additionally, a comparison of these results to the extrapolation model of Chou is given.

Physics and Chemistry of Liquids, 2007

The In1−xBix (x = 0.40, 0.34, 0.23, 0.13, 0.09) molten alloys have been studied by means of visco... more The In1−xBix (x = 0.40, 0.34, 0.23, 0.13, 0.09) molten alloys have been studied by means of viscosity measurements and X-ray diffraction method. Temperature dependence of viscosity coefficient shows the Arrhenius like behavior with anomalous in form of local maximum and significant scattering of experimental values. The features in temperature dependencies of viscosity coefficient were studied also by means of X-ray diffraction method.

Physics and Chemistry of Liquids, 2014

Shear viscosity measurements were performed for liquid Co-Sn alloys over a wide temperature range... more Shear viscosity measurements were performed for liquid Co-Sn alloys over a wide temperature range above the respective liquidus temperatures. A high temperature oscillating-cup viscometer was used. It was found experimentally that viscosity as a function of temperature obeys an Arrhenius law. The data were compared with calculated values, obtained from different thermodynamic approaches. A good agreement was found between experimental results and calculated ones by the Budai-Benkö-Kaptay model.

Journal of Nuclear Materials, 2013

Lead-gold eutectic alloy is under consideration as target material of spallation sources. The the... more Lead-gold eutectic alloy is under consideration as target material of spallation sources. The thermohydraulic design of such a target or related coolant systems requires a reliable data basis regarding the temperature dependent physical properties of such alloys. We present measurements of the electrical and thermal conductivity, thermoelectric power, viscosity and surface tension for liquid P b 84.1 Au 15.9 alloy of eutectic composition in a wide temperature range between the melting point and about 1000 K.

Structure of liquid Sb-Sn alloys were studied by means of viscosity measurements and X-ray diffra... more Structure of liquid Sb-Sn alloys were studied by means of viscosity measurements and X-ray diffraction. Structural factors and pair correlation functions were analysed and interpreted using the random atomic distribution model. The features of temperature dependence of the viscosity coefficient were analysed taking into account X-ray diffraction patterns. The results allow us to conclude that Sb atoms substitute for Sn atoms, forming a typical atomic solution, which reveals chemical and topological short-range order. Moreover, certain atoms form Sband Sn-based SbnSnm associates and self-associates.

Journal of Physical Studies, 2008

The viscosity of Al1−xNix (x = 0.025; 0.05 and 0.075) molten alloys has been studied by means of ... more The viscosity of Al1−xNix (x = 0.025; 0.05 and 0.075) molten alloys has been studied by means of oscillating crucible method. The temperature dependence of dynamical viscosity coefficient is obtained and activation energy is estimated from them. The analysis of concentration dependence of viscosity coefficient reveals its deviation from linear dependence. Significant increase of viscosity coefficient for liquid aluminum upon the addition of Ni-atoms is caused by cluster formation and increase of their size.

High Temperatures-High Pressures, 2020

In this study, some structure-sensitive thermophysical properties, namely, thermal conductivity, ... more In this study, some structure-sensitive thermophysical properties, namely, thermal conductivity, thermoelectric power, density and surface tension of liquid AlCu4TiMg alloy, as one of the most promising cast alloys to fabricate components for cars, aircraft and other complex engineering products, were investigated. Thermoelectric power was measured in a wide temperature range by the four-point contact method. Thermal conductivity was investigated by the steady-state concentric cylinder method. The oscillating drop technique combined with electromagnetic levitation was used for density and surface tension studies. The results obtained are compared with experimental and calculated data from literature for pure aluminum.

Applied Nanoscience, 2020

The effect of bimetallic monodisperse CoPd nanoparticles on the microstructure and the shear stre... more The effect of bimetallic monodisperse CoPd nanoparticles on the microstructure and the shear strength of the Cu/ SAC305/ Cu solder joint was investigated. The nanocomposite Sn-3.0Ag-0.5Cu (SAC305) solders with 0.1, 0.3, 0.5, and 1.0 wt% nanoCoPd were prepared through a paste mixing method. The employed bimetallic nanoparticles were produced via a modified oleylamine method. The microstructural analysis of as-solidified Cu/solder/Cu joints was performed by scanning electron microscopy. The results showed that initial additions of CoPd nanoparticles into the SAC305 solder promoted the growth of the interfacial planar-type Cu 3 Sn IMC layer; while the average thickness of the interfacial scallop-type Cu 6 Sn 5 IMC layer slightly decreased. Further additions of the nanosized CoPd admixtures to the SAC305 solder paste lead to a significant increase of the average thickness of the Cu 6 Sn 5 intermetallic compound layer up to 40%. The shear strength measurements were performed to investigate a relationship between the microstructure and mechanical properties of the investigated solder joints. The results indicated a decrease in the shear strength of the SAC305 solder joint by addition of 0.1 wt% CoPd NPs, while a difference in absolute values between solder joints with 0.3, 0.5, and 1.0 wt% nanoCoPd was practically insignificant.

Chemistry of Metals and Alloys, 2008

The enthalpy of mixing of binary In-Bi melts was measured by means of a calorimetric method at T ... more The enthalpy of mixing of binary In-Bi melts was measured by means of a calorimetric method at T = 1023, 875, 483 K. Its concentration dependence reveals a flat minimum in the region between the intermetallic phases InBi and In 2 Bi. The shape of the curve of the integral enthalpy of mixing for liquid In-Bi alloys is in agreement with the assumption of a competition between InBi-and In 2 Bi-like chemical ordering before solidification. Enthalpy of mixing / In-Bi molten alloys / Intermetallic phase / Associate

RSC Advances, 2018

Difference in the enthalpy effect by replacing micro- by nano-sized particles in drop calorimetry.

Journal of Molecular Liquids, 2018

The impact of minor additions of Ni nanoparticles on the dynamic viscosity of the liquid Sn-3.0Ag... more The impact of minor additions of Ni nanoparticles on the dynamic viscosity of the liquid Sn-3.0Ag-0.5Cu alloy (SAC305; in wt.%) is examined. The nanocomposite samples were prepared from commercial SAC305 powder and Ni nanopowder by cold pressing. The dynamic viscosity of the (Sn96.5Ag3.0Cu0.5)100-xNix alloys measured during heating and cooling exhibited a hysteresis in a temperature range up to 100 K above the melting temperature. This is supposed to be related to the structural transformations caused by dissolution of Ni nanoparticles in the liquid Sn-based matrix upon heating. The experimental values of the viscosity of the (Sn96.5Ag3.0Cu0.5)100-xNix alloys are in a good agreement with calculated data using thermodynamic approaches.

Metallurgical and Materials Transactions A, 2018

The density of the liquid equiatomic high-entropy alloys, namely, AlCoCrCuFeNi, AlCoCu-FeNi, and ... more The density of the liquid equiatomic high-entropy alloys, namely, AlCoCrCuFeNi, AlCoCu-FeNi, and CrCoCuFeNi, as well as quaternary alloys AlCoCuFe and AlCoCrNi was determined over a wide temperature range. The measurements were performed by a non-contact technique combining electromagnetic levitation and optical dilatometry. The temperature and composition dependencies of the density were analyzed and the molar excess volumes were calculated. The integral enthalpy of mixing of multi-component alloys was predicted using extended Kohler's model, while Miedema's model was used for binary subsystem alloys. It has been found that a negative excess volume of the investigated Al-containing liquid alloys correlates with a negative enthalpy of mixing. In contrast, a positive excess volume and an endothermic reaction have been estimated for the liquid CoCrCuFeNi alloy. The change of the excess volume in the Al-containing liquid alloys is affected by two basic effects, namely, compression of the Al matrix and formation of compounds in the melt.

Materials Chemistry and Physics, 2016

SnAg -Cu (SAC) alloys are commonly recognized as lead-free solders employed in the electronics in... more SnAg -Cu (SAC) alloys are commonly recognized as lead-free solders employed in the electronics industry. However, some disadvantages in mechanical properties and their higher melting temperatures compared to Pb-Sn solders prompt new research relating to reinforcement of existing SAC solders. One of the ways to reinforce these solder materials is the formation of composites with nanoparticles as filler materials. Accordingly, this study presents structural features of nanocomposite (Sn-3.0Ag-0.5Cu) 100-x (nanoCo) x solders with up to 0.8 wt.% nano Co. The effect of nano-sized Co particles was investigated by means of differential thermal analysis (DTA), X-ray diffraction (XRD) in both liquid and solid states, and scanning electron microscopy (SEM). The experimental data of DTA are compared with available literature data for bulk Sn-3.0Ag-0.5Cu alloy to check the capability of minor nanoinclusions to decrease the melting temperature of the SAC solder. The combination of structural data in liquid and solid states provides important information about the structural transformations of liquid Sn-3.0Ag-0.5Cu alloys caused by minor Co additions and the phase formation during crystallization. Furthermore, scanning electron microscopy has shown the mutual substitution of Co and Cu atoms in the Cu 6 Sn 5 and CoSn 3 phases, respectively.

Journal of Mining and Metallurgy, Section B: Metallurgy, 2017

In this study, some structure-sensitive thermophysical properties, namely, electrical conductivit... more In this study, some structure-sensitive thermophysical properties, namely, electrical conductivity, thermal conductivity and thermoelectric power of liquid binary alloys Al33.3Mg66.7, Mg47.6Zn52.4 and Mg33.3Zn66.7 (all in wt.%), as the most promising cast alloys to fabricate components for cars, aircraft and other complex engineering products, were investigated. The electrical conductivity and thermoelectric power were measured in a wide temperature range by the four-point contact method. The thermal conductivity was measured by the steady-state concentric cylinder method. The obtained results are compared with literature experimental and calculated data.

Journal of Electronic Materials, 2016

Although considerable research has been dedicated to the synthesis and characterization of lead-f... more Although considerable research has been dedicated to the synthesis and characterization of lead-free nanoparticle solder alloys, only very little has been reported on the reliability of the respective joints. In fact, the merit of nanoparticle solders with depressed melting temperatures close to the Sn-Pb eutectic temperature has always been challenged when compared with conventional solder joints, especially in terms of inferior solderability due to the oxide shell commonly present on the nanoparticles, as well as due to compatibility problems with common fluxing agents. Correspondingly, in the current study, SnAg -Cu (SAC) nanoparticle alloys were combined with a proper fluxing vehicle to produce prototype nanosolder pastes. The reliability of the solder joints was successively investigated by means of electron microscopy and mechanical tests. As a result, the optimized condition for employing nanoparticles as a competent nanopaste and a novel procedure for surface treatment of the SAC nanoparticles to diminish the oxide shell prior to soldering are being proposed.

The Journal of Physical Chemistry C, 2016

Heat effects for the addition of Co in bulk and nanosized forms into the liquid Sn-3.8Ag-0.7Cu al... more Heat effects for the addition of Co in bulk and nanosized forms into the liquid Sn-3.8Ag-0.7Cu alloy were studied using drop calorimetry at four temperatures between 673 and 1173 K. Significant differences in the heat effects between nano and bulk Co additions were observed. The considerably more exothermic values of the measured enthalpy for nano Co additions are connected with the loss of the surface enthalpy of the nanoparticles due to the elimination of the surface of the nanoparticles upon their dissolution in the liquid alloy. This effect is shown to be independent of the calorimeter temperature (it depends only on the dropping temperature through the temperature dependence of the surface energy of the nanoparticles). Integral and partial enthalpies of mixing for Co in the liquid SAC-alloy were evaluated from the experimental data.

Physics and Chemistry of Liquids, 2015

ABSTRACT The Co–Sn system is an important subsystem for Sn-based anode materials of lithium-ion b... more ABSTRACT The Co–Sn system is an important subsystem for Sn-based anode materials of lithium-ion batteries. Experimental results on the physical–chemical properties of this system in the liquid state, however, are rather sparse. In this work, the atomic structure and structure-sensitive thermophysical properties (viscosity, electrical resistivity, and thermoelectric power) of liquid Co–Sn alloys were investigated in a wide temperature range with special attention to the melting-solidification region. The obtained experimental results were combined with differential thermal analysis (DTA) data in order to verify the liquidus curve in the Sn-rich part of the Co–Sn phase diagram.

Journal of Alloys and Compounds, 2014

An analysis of the structure features of liquid Co-Sn alloys has been performed by means of X-ray... more An analysis of the structure features of liquid Co-Sn alloys has been performed by means of X-ray diffraction method, viscosity coefficient analysis and computer simulation method. The X-ray diffraction investigations were carried out over a wide concentration range at the temperature 1473 K. It was found that the structure of these alloys can be described in the frame of independent X-ray scattering model. The viscosity coefficient was calculated by an excess entropy scaling and compared with experimental data.

Inorganic Materials, 2010

The viscosity of Sb-Sn melts containing 0, 5, 10, and 20 at % antimony has been measured as a fun... more The viscosity of Sb-Sn melts containing 0, 5, 10, and 20 at % antimony has been measured as a function of temperature by the oscillating cylinder method. The composition and temperature dependences of the viscosity coefficient deviate from classical theory predictions. The anomalous behavior is interpreted in terms of melt structure and changes in short range order. Structural changes in the Sb-Sn melts are assumed to lead to an anomalous increase in viscosity coefficient.

Monatshefte für Chemie - Chemical Monthly, 2014

The partial and integral molar enthalpies of mixing of liquid Co-Li-Sn alloys were determined usi... more The partial and integral molar enthalpies of mixing of liquid Co-Li-Sn alloys were determined using drop calorimetry. The investigations were performed along six sections by the addition of lithium to mixtures with the compositions x Co /x Sn & 2:98, x Co /x Sn & 1:9, and x Co /x Sn & 3:17 as well as by the addition of cobalt to mixtures with the compositions x Li /x Sn & 3:17, x Li /x Sn & 1:2, and x Li /x Sn & 1:1 at a temperature of 1,173 K. The Co-Li-Sn system shows exothermic behavior of the integral molar enthalpy of mixing in the investigated concentration range. The integral molar enthalpy of mixing of liquid Co-Li system was calculated by Miedema's model to fit our measured ternary data using an extended Redlich-Kister-Muggianu model for substitutional solutions.

The Journal of Chemical Thermodynamics, 2013

Integral molar enthalpies of mixing were determined by drop calorimetry for Cu-Li-Sn at 1073 K al... more Integral molar enthalpies of mixing were determined by drop calorimetry for Cu-Li-Sn at 1073 K along five sections x Cu /x Sn % 1:1, x Cu /x Sn % 2:3, x Cu /x Sn % 1:4, x Li /x Sn % 1:1, and x Li /x Sn % 1:4. The integral and partial molar mixing enthalpies of Cu-Li and Li-Sn were measured at the same temperature, for Li-Sn in addition at 773 K. All binary data could be described by Redlich-Kister-polynomials. Cu-Li shows an endothermic mixing effect with a maximum in the integral molar mixing enthalpy of 5300JAˊmolAˋ1atxCu=0.5,Li−Snanexothermicminimumof5300 J Á mol À1 at x Cu = 0.5, Li-Sn an exothermic minimum of 5300JAˊmolAˋ1atxCu=0.5,Li−Snanexothermicminimumof À37,000 J Á mol À1 at x Sn $ 0.2. For Li-Sn no significant temperature dependence between 773 K and 1073 K could be deduced. Our measured ternary data were fitted on the basis of an extended Redlich-Kister-Muggianu model for substitutional solutions. Additionally, a comparison of these results to the extrapolation model of Chou is given.

Physics and Chemistry of Liquids, 2007

The In1−xBix (x = 0.40, 0.34, 0.23, 0.13, 0.09) molten alloys have been studied by means of visco... more The In1−xBix (x = 0.40, 0.34, 0.23, 0.13, 0.09) molten alloys have been studied by means of viscosity measurements and X-ray diffraction method. Temperature dependence of viscosity coefficient shows the Arrhenius like behavior with anomalous in form of local maximum and significant scattering of experimental values. The features in temperature dependencies of viscosity coefficient were studied also by means of X-ray diffraction method.

Physics and Chemistry of Liquids, 2014

Shear viscosity measurements were performed for liquid Co-Sn alloys over a wide temperature range... more Shear viscosity measurements were performed for liquid Co-Sn alloys over a wide temperature range above the respective liquidus temperatures. A high temperature oscillating-cup viscometer was used. It was found experimentally that viscosity as a function of temperature obeys an Arrhenius law. The data were compared with calculated values, obtained from different thermodynamic approaches. A good agreement was found between experimental results and calculated ones by the Budai-Benkö-Kaptay model.

Journal of Nuclear Materials, 2013

Lead-gold eutectic alloy is under consideration as target material of spallation sources. The the... more Lead-gold eutectic alloy is under consideration as target material of spallation sources. The thermohydraulic design of such a target or related coolant systems requires a reliable data basis regarding the temperature dependent physical properties of such alloys. We present measurements of the electrical and thermal conductivity, thermoelectric power, viscosity and surface tension for liquid P b 84.1 Au 15.9 alloy of eutectic composition in a wide temperature range between the melting point and about 1000 K.