Structural changes in molten CdTe

Shear viscosity (h) measurements of CdTe and CdTe + 2 at% In melts were performed using a cup viscometer up to 1403 K. The h(T) dependencies obtained during slow heating and cooling (Vh/c = = 10-15 K/h) show hysteresys near a melting point. According to the η(T) dependencies data drastic changes the melts structure occurred at 1376 K both during the heating and cooling of the melts

The influence of silver content on structure and properties of Sn-Bi-Ag solder and Cu/solder/Cu joints

The authors gratefully acknowledge the financial support of the Slovak Grant Agency under the Contracts VEGA 2/6160/26 and 2/0111/11. This work was also supported by the Slovak Research and Development Agency under the Contracts APVV-0102-07, APVV-0076-11, APVV-0492-11 and APVV-SK-UA-0043-09 and by CEX FUN-MAT. V.S. gratefully acknowledges the fellowship of the Slovak Academic Information Agency. This research contributes to the European COST Action MP0602 on Advanced Solder Materials for High Temperature Applications.The effect of silver content on structure and properties of Sn100-xBi10Agx (x=3-10 at%) lead-free solder and Cu-solder-Cu joints was investigated. The microstructure of the solder in both bulk and rapidly solidified ribbon forms was analyzed by scanning electron microscopy (SEM) and X-ray diffraction. The peculiarities in melting kinetic, studied by differential scanning calorimetry (DSC), and silver influence on it are described and discussed. The wetting of a copper substrate was examined by the sessile drop method in the temperature range of 553-673 K in air and deoxidizing gas (N-2+10%H-2) at atmospheric pressure. Cu-solder-Cu joints were also prepared in both atmospheres, and their shear strength was measured by the push-off method. The produced solders consisted of tin, bismuth and Ag3Sn phases. The product of the interaction between the solder and the copper substrate consists of two phases: Cu3Sn, which is adjacent to the substrate, and a Cu6Sn5 phase. The wetting angle in air increased slightly as the silver concentration in the solder increased. Wetting of the copper substrate in N-2+10H(2) gas shows the opposite tendency: the wetting angle slightly decreased as the silver content in the solder increased. The shear strength of the joints prepared in air (using flux) tends to decrease with increasing production temperature and increasing silver content in the solder. The equivalent decrease in the shear strength of the joints prepared in N-2+10H(2) is more apparent. (C) 2013 Elsevier B.V. All rights reserved

Physical properties of the eutectic NaF-LiF-LaF3 melt ionic liquid system

Results of experimental studies on electrical conductivity, viscosity and thermo-electromotive force temperature dependencies of eutectic NaF-LiF-LaF3 melt ionic liquid mixture in the temperature range of (580 ÷ 800) °C are presented. It has been found, that at the temperature of (675 ± 5) °C the ionic mixture thermo-electromotive force changes its sing to reverse, with this change being correlated with viscosity temperature dependence type readjustment occurring at the same temperature. It has been shown that the maximum value of liquid ionic mixture electrical conductivity is achieved at the temperature of (750 ± 5) °C. Obtained results could help in the molten salt reactor blanket design

The influence of silver content on structure and properties of Sn-Bi-Ag solder and Cu/solder/Cu joints

The authors gratefully acknowledge the financial support of the Slovak Grant Agency under the Contracts VEGA 2/6160/26 and 2/0111/11. This work was also supported by the Slovak Research and Development Agency under the Contracts APVV-0102-07, APVV-0076-11, APVV-0492-11 and APVV-SK-UA-0043-09 and by CEX FUN-MAT. V.S. gratefully acknowledges the fellowship of the Slovak Academic Information Agency. This research contributes to the European COST Action MP0602 on Advanced Solder Materials for High Temperature Applications.The effect of silver content on structure and properties of Sn100-xBi10Agx (x=3-10 at%) lead-free solder and Cu-solder-Cu joints was investigated. The microstructure of the solder in both bulk and rapidly solidified ribbon forms was analyzed by scanning electron microscopy (SEM) and X-ray diffraction. The peculiarities in melting kinetic, studied by differential scanning calorimetry (DSC), and silver influence on it are described and discussed. The wetting of a copper substrate was examined by the sessile drop method in the temperature range of 553-673 K in air and deoxidizing gas (N-2+10%H-2) at atmospheric pressure. Cu-solder-Cu joints were also prepared in both atmospheres, and their shear strength was measured by the push-off method. The produced solders consisted of tin, bismuth and Ag3Sn phases. The product of the interaction between the solder and the copper substrate consists of two phases: Cu3Sn, which is adjacent to the substrate, and a Cu6Sn5 phase. The wetting angle in air increased slightly as the silver concentration in the solder increased. Wetting of the copper substrate in N-2+10H(2) gas shows the opposite tendency: the wetting angle slightly decreased as the silver content in the solder increased. The shear strength of the joints prepared in air (using flux) tends to decrease with increasing production temperature and increasing silver content in the solder. The equivalent decrease in the shear strength of the joints prepared in N-2+10H(2) is more apparent. (C) 2013 Elsevier B.V. All rights reserved

Influence of the composition to the physical properties of NaF-LiF-LaF3 melt liquid systems

Influence of the chemical composition of NaF-LiF-LaF3 system on temperature dependence of electrical con-ductivity, viscosity and thermoelectric power has been studied in a wide temperature range between 600 and 1500 К. The obtained results could help in design of the molten salt reactor blanket

Structure and electric resistance of Sn-Cu(Ag) solders in the precrystallization temperature range

This work was partially supported by the State Foundation for Fundamental Research (Project No. F-28.3/024).We investigate the atomic structure of tin-based solders by X-ray diffraction methods and the reverse Monte Carlo method. Total and partial structural factors and pair correlation functions are calculated. It is shown that Sn0.987Cu0.013, Sn0.962Ag0.038, and Sn0.949Ag0.038Cu0.013 liquid alloys are characterized by a microinhomogeneous structure with Cu(Ag)-Sn clusters distributed in the tin-based matrix