Metal deposited nanoparticles as "bridge materials" for lead-free solder nanocomposites.

An influence of carbon nanotubes and carbon nanospheres coated by Au-Pd and Pt on the microstructure of solder/copper joints at room temperature and after aging at sub-zero temperature. The carbon nanosized admixtures were mixed with ternary Sn3.0Ag0.

Hybrid solder joints: the effect of nanosized ZrO particles on morphology of as-reflowed and thermally aged Sn-3.5Ag solder joints.

The main number of current researches has been focused on the microstructure and mechanical properties of the Sn-based Sn-Ag-Cu-based solders, while various kinds of nanosized particles have been added. The synthesis and handling of ceramic nanosized powder are much easier than of metal nanoparticles. In addition, metal nanoparticles solved in solder joints during the soldering process or by thermal aging could behave as an alloying element similar to bulk metal additions, while ceramic nanoparticles retain their chemically inactive behavior in various thermal, thermo-mechanical, and electrical constraints.

Lightweight magnesium nanocomposites: electrical conductivity of liquid magnesium doped by CoPd nanoparticles.

The effect of monodisperse bimetallic CoPd NP admixtures on the electrical conductivity of liquid magnesium was studied. Temperature dependence of the electrical conductivity of liquid Mg(CoPd), Mg(CoPd), and Mg(CoPd) alloys was measured in a wide temperature range above the melting point by a four-point method. It was shown that the addition of even small amount of CoPd nanoparticles to liquid Mg has a significant effect on the electrical properties of the melts obtained.

The nano heat effect of replacing macro-particles by nano-particles in drop calorimetry: the case of core/shell metal/oxide nano-particles.

Experimental results are presented here obtained by a drop calorimetric method, in which Ni and Cu particles, both in bulk and nanosized form, were dropped into a liquid Sn-3.8Ag-0.7Cu solder alloy (in wt%).

Synthesis and Characterization of Pure Ni and Ni-Sn Intermetallic Nanoparticles.

The present research focused on the synthesis of Ni and Ni-Sn nanoparticles via a chemical reduction method using hydrazine hydrate. The syntheses were performed applying highly purified water or diethylene glycol as solvent. The produced nanoparticles were characterized by scanning electron microscopy and powder X-ray diffraction.

Microstructure and Electro-Physical Properties of Sn-3.0Ag-0.5Cu Nanocomposite Solder Reinforced with Ni Nanoparticles in the Melting-Solidification Temperature Range.

The electrical conductivity of nanocomposite Sn-3.0Ag-0.5Cu alloys with two different weight percentages of Ni nanoparticles (1.

Viscosity and Electrical Conductivity of the Liquid Sn-3.8Ag-0.7Cu Alloy with Minor Co Admixtures.

The viscosity and electrical conductivity as structure-sensitive transport properties of the liquid metals and alloys are important for modeling of the melting and solidification processes. The viscosity and electrical conductivity data provide additional information about the influence of impurities on the structure and physicochemical properties of the liquid metal matrix, which is useful for understanding of structural transformations in the liquid state. In the present work, an impact of minor Co admixtures on the viscosity and electrical conductivity of liquid Sn-3.

Enthalpy Effect of Adding Cobalt to Liquid Sn-3.8Ag-0.7Cu Lead-Free Solder Alloy: Difference between Bulk and Nanosized Cobalt.

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.

Sn-Ag-Cu nanosolders: Melting behavior and phase diagram prediction in the Sn-rich corner of the ternary system.

Melting temperatures of Sn-Ag-Cu (SAC) alloys in the Sn-rich corner are of interest for lead-free soldering. At the same time, nanoparticle solders with depressed melting temperatures close to the Sn-Pb eutectic temperature have received increasing attention. Recently, the phase stability of nanoparticles has been the subject of plenty of theoretical and empirical investigations.

Synthesis and thermal behavior of tin-based alloy (Sn-Ag-Cu) nanoparticles.

The prominent melting point depression of nanoparticles has been the subject of a considerable amount of research. For their promising applications in electronics, tin-based nano-alloys such as near-eutectic Sn-Ag-Cu (SAC) alloys have been synthesized via various techniques. However, due to issues such as particle aggregation and oxidation or introduced impurities, the application of these nano-size particles has been confined or aborted.

Structural studies of liquid Co-Sn alloys.

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.

Enthalpy of mixing of liquid Co-Sn alloys.

A literature overview of enthalpy of mixing data for liquid Co-Sn alloys shows large scattering but no clear temperature dependence. Therefore drop calorimetry was performed in the Co-Sn system at twelve different temperatures in 100 K steps in the temperature range (673 to 1773) K. The integral enthalpy of mixing was determined starting from 1173 K and fitted to a standard Redlich-Kister polynomial.

Viscosity of liquid Co-Sn alloys: thermodynamic evaluation and experiment.

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 Enthalpies of Mixing of Liquid Ni-Sn-Zn Alloys.

The partial and integral enthalpies of mixing of liquid ternary Ni-Sn-Zn alloys were determined. The system was investigated along two sections / ≈ 1:9, / ≈ 1:6 at 1073 K and along two sections / ≈ 9:1, / ≈ 4:1 at 873 K. The integral enthalpy of mixing at each temperature is described using the Redlich-Kister-Muggianu model for substitutional ternary solutions.

Enthalpies of mixing of liquid ternary Co-Li-Sn alloys.

Abstract: 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 [Formula: see text]/[Formula: see text] ≈ 2:98, [Formula: see text]/[Formula: see text] ≈ 1:9, and [Formula: see text]/[Formula: see text] ≈ 3:17 as well as by the addition of cobalt to mixtures with the compositions [Formula: see text]/[Formula: see text] ≈ 3:17, [Formula: see text]/[Formula: see text] ≈ 1:2, and [Formula: see text]/[Formula: see text] ≈ 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.

Calorimetric studies of Cu-Li, Li-Sn, and Cu-Li-Sn.

Integral molar enthalpies of mixing were determined by drop calorimetry for Cu-Li-Sn at 1073 K along five sections / ≈ 1:1, / ≈ 2:3, / ≈ 1:4, / ≈ 1:1, and / ≈ 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.