Sn Binary Alloys Research Articles

Strength-ductility synergy of Mg-7.5 wt.% Sn binary alloys promoted by semisolid isothermal treatment coupled with hot extrusion

In this paper, we propose to adopt a new process for as-extruded Mg-7.5wt.%Sn binary alloy, i.e., semisolid isothermal heat treatment coupled with hot extrusion. Semi-solid isothermal treatment achieved nanosizing of micron-layer lamellar eutectic in the Mg-7.5wt.% Sn binary alloy, while subsequent hot extrusion crushed this nanoeutectic to nanoparticles, resulting in high strength (303 ± 2.8MPa for UTS and 246 ± 0.7MPa for YS,) and high elongation (11.5 ± 0.1% for EL) of the Mg-7.5wt.% Sn binary alloy. Grain refinement, multi-scale particles (broken nanoscale and submicron particles, and dynamically precipitated nanoscale phases), and high-density dislocations are the main contributors to the high strength. Meanwhile, the good ductility of the alloy is promoted by the softening effect due to dynamic recrystallisation as well as the weakening and random distribution of the texture.

Calorimetric measurements of Ga–In, Ga–Sn, and In–Sn binary alloy systems as sustainable lead-free solder alternatives

Calorimetric measurements of Ga–In, Ga–Sn, and In–Sn binary alloy systems as sustainable lead-free solder alternatives

Clean and efficient recovery of In–Sn and In–Sn–Bi lead-free brazing materials by vacuum volatilization and thermodynamic modeling

In this study, a novel method was proposed for the clean and efficient recovery of high-value-added In–Sn and In–Sn–Bi alloys. Vacuum volatilization of the In–Sn binary alloy was conducted in a temperature range of 1373–1573 K with a system pressure of 5 Pa. The results showed that In and Sn were effectively separated. The Sn content in the residue was 99.9908%, and the In content in the volatile fraction reached 99.66%. Vacuum volatilization of the In–Sn–Bi ternary alloy was conducted out at 1073–1373 K and 5 Pa. The results showed that Bi could be separated from In and Sn, the Bi content in the residue decreased from 32.5% to 3.88%, and the Bi content in the volatile fraction reached 95.67%. The residual In–Sn alloy could be effectively separated by vacuum volatilization. The MIVM, M-MIVM, Wilson equation and NRTL were used to calculate and analyze the activity and activity coefficients of In–Sn, In–Bi, Sn–Bi and In–Sn–Bi alloy elements, respectively, and the results showed that M-MIVM had the highest prediction accuracy. The vapor-liquid equilibrium (VLE) data of the In–Sn, In–Bi, Sn–Bi, and In–Sn–Bi alloys were predicted, and the corresponding VLE phase diagrams were plotted based on the M-MIVM and VLE theory. The predicted VLE values were in good agreement with the corresponding experimental data determined in this study, indicating that the M-MIVM was reliable for indium-based alloys. The results of this work provided reliable experimental data and a thermodynamic model for the VLE study of In-based alloys, opening a new technique for the clean and efficient recycling of binary and multicomponent In-based alloys.

Fast Na-diffusive tin alloy for all-solid-state Na-based batteries

A metastable-phase Na–Sn binary alloy exhibiting exceptionally high Na diffusivity at room temperature (D25 = 5.4 × 10−7 cm2 s−1) was applied to a next-generation all-solid-state sodium battery, achieving ultralow energy loss properties.

Calorimetry of the Melting and Solidification Processes in the Eutectics of Pb–Cd, Pb–Sn, Pb–Bi, and Cd–Sn Binary Alloys

Calorimetry of the Melting and Solidification Processes in the Eutectics of Pb–Cd, Pb–Sn, Pb–Bi, and Cd–Sn Binary Alloys

Numerical simulation analysis on solute redistribution of In–1 wt% Sn alloy during multipass vertical zone refining process

Horizontal zone refining has been widely used for the production of ultra-pure metals through solidification-induced microsegregation effect. Current research on vertical zone refining is limited, owing to the high-temperature cracking risk of crucible; however, it is highly potential for low-melting metals as demonstrated in this research. The present work comprehensively dealt with both back-diffusion and coarsening effect on the solute redistribution by adopting the Voller-Beckerman (V-B) model. Physical fields, including temperature, melt flow and solute distribution, were numerically simulated based on In–1 wt.%Sn binary alloy by means of finite volume method, and the dynamic interaction between melt-flow and solute distribution was clarified. A high-efficiency processing routine was suggested, and it was experimentally proved that the vertical zone refining was a promising method for producing ultra-pure 7 N-grade indium.

Superconductivity of the Bi–Sn Eutectic Alloy

We report on the results of investigations of superconductivity in the Bi–Sn binary alloy with a eutectic concentration of 57 wt % of Bi and 43 wt % of Sn. The temperature and field dependences of the dc magnetization have been measured in the range of 1.8–20 K in magnetic fields of up to 20 kOe using a Quantum Design MPMS3 SQUID magnetometer. A two-stage phase transition with diamagnetism establishment temperatures of 8.55 and 5.1 K has been found. A phase diagram has been built. The coherence length for the first stage has been estimated. The field dependence of the irreversibility temperature has been determined. Positive curvature portions observed in the critical dependences have been interpreted using a model based on the proximity effect.

The electrodeposition of low-Sn imitation gold Cu–Sn alloy from EDTA-tartrate double complexing agents

The electrodeposition of a Cu–Sn binary alloy on stainless steel from a cyanide-free alkaline electrolyte containing EDTA·2Na and C4H4O6KNa was investigated to explore the possibility of a cyanide-free double complexing system that maintains the decorative quality and coating performance. The Cu–Sn co-deposition occurred at −0.95 Vvs.Hg|HgO, and the height of cathode peak A from the BR bath was −0.0280 A. EDTA·2Na could simultaneously complex with Cu ions and Sn ions, while C4H4O6KNa could only complex with Cu ions, which was shown through the analysis of the cyclic voltammetry (CV) curves together with the nuclear magnetic resonance (NMR) results. The molar concentration ratio and sum of the two main salts or the two complexing agents, and the pH of the electroplating solutions were shown to influence the surface micromorphology, composition and phase structure of the Cu–Sn coatings. The scanning electron microscopy (SEM) analysis showed that the Cu–Sn coating obtained from the bath with EDTA-tartrate double complexing agents exhibited smaller grain sizes than that obtained from the bath with the single EDTA or tartrate complexing agent, and the smallest grain size of 0.2 μm was obtained from the BR bath. In addition to being smaller than the others, this coating contained uniform particle sizes. The energy-dispersive X-ray spectroscopy (EDS) analysis indicated that the composition of the Cu–Sn coating obtained from the BR bath was 92.8 wt% Cu and 7.2 wt% Sn, and this coating was golden in colour. X-ray diffraction (XRD) showed that the Cu–Sn coatings were crystalline and were composed of a mixture of Cu, Cu6Sn5, [Cu, Sn] and Cu10Sn3 phases, indicating the formation of Cu–Sn binary alloy. These results may provide theoretical guidance for the electrodeposition technology of other alloy coatings.

Energetics of binary Zr–Nb, Zr–Sn and Nb–Sn alloys and solute-vacancy binding: DFT calculations

The structural and energetic properties of Zr–Sn, Zr–Nb and Nb–Sn binary alloys with different concentration of elements and symmetry of the crystal lattice are studied by using density functional theory. The possibility of different alloying additions to dissolve/segregate in a host matrix is analyzed. The stability of different phases of Zr–Sn, Zr–Nb and Nb–Sn binary alloys with various concentration of alloying elements is discussed. The binding vacancy-impurity energy is calculated. The ability of different impurities to trap single vacancy different alloys is discussed in detail.

Fabrication of (Ba,K)Fe2As2 tapes by ex situ PIT process using Ag-Sn alloy single sheath

Instead of ordinal pure Ag, Ag-based Sn binary alloys (up to 7.5 at%Sn) with higher mechanical strength are used for the sheath material of ex situ powder-in-tube (PIT)-processed (Ba,K)Fe2As2(Ba-122) tapes. We found that the use of the Ag-Sn alloy enhances the densification and texturing of the Ba-122 core, resulting in higher transport, Jc. Moreover, the optimum heat treatment temperature for a high Jc can be lowered by around 100 °C due to the higher packing density of the Ba-122 core prior to the final heat treatment. We also found that the smoothness of the interface between the sheath and Ba-122 core is significantly improved by using the Ag-Sn binary alloy sheaths. These results show that the Ag-Sn alloy is promising as a sheath material in PIT-processed Ba-122 superconducting wires.

Study of the influence of the trisodium nitrilotriacetic as a complexing agent on the copper, tin and zinc co-deposition, morphology, chemical composition and structure of electrodeposits

The electrodeposition of Cu–Sn–Zn ternary alloys on to AISI 1010 steel from an acid bath, pH4.99, containing trisodium nitrilotriacetic (NTA) was investigated, with different proportions of the metal ions in the baths. The Cu–Sn–Zn voltammetric profile showed four cathodic regions, irrespective of bath composition. The first three regions were associated with the reduction of the Cu-NTA and Sn-NTA complexes, and in the last region with Cu-NTA, Sn-NTA and Zn-NTA complexes reduction, attributed through of the analysis of the voltammetric curves together with the energy-dispersive X-ray spectroscopy (EDS) results. EDS analysis showed that only in cathodic region c4 occurred the transition from Cu–Sn binary alloy to Cu–Sn–Zn ternary alloy, regardless of bath composition. In addition, Cu–Sn–Zn co-deposition, at Ed−1.60V (cathodic region c4), was normal regardless of bath composition. Analysis of the photomicrographs of Cu–Sn–Zn electrodeposits obtained at electrodeposition potential (Ed) –1.60V, with electrodeposition charge density (qd) of 3.0Ccm−2, from 0.20Cu2+/0.050Sn2+/0.050Zn2+ bath presented the highest grain size (0.77μm) and from 0.15Cu2+/0.075Sn2+/0.075Zn2+ bath presented smaller grain size (0.27μm), all formed by irregular crystallites. Adhesion test showed that the Cu–Sn–Zn electrodeposit obtained at Ed−1.60V, with qd 3.0Ccm−2, from 0.10Cu2+/0.10Sn2+/0.10Zn2+ bath presented a good adherence to the 1010 steel substrate, being classified as Gr2. Laser scanning confocal microscopy (LSCM) showed that roughness increased from 1.48μm to 2.98μm when Cu2+ ions concentration in the electrodeposition baths decreased. X-ray diffraction pattern indicated that the Cu–Sn–Zn electrodeposits produced at Ed−1.60V with qd 3.0Ccm−2, depending on bath composition, presented structure crystalline with a mixture of Sn, SnO, CuZn, Cu5Zn8, η-Cu6Sn5 and Cu20Sn6 phases, indicating the formation of Cu–Sn–Zn ternary alloy.

Effect of Sn content and texture on the twinning behaviour of Zr–Sn binary alloys at low temperature

The present study is concerned with the twinning behaviour of Zr–Sn alloys at low temperature as a function of Sn content and starting texture. Zr–Sn samples, with Sn contents in the range of 0.33–2.9 wt. % and with different initial textures were subjected to uniaxial compression tests at −80 °C. Sn was found to enhance the {101¯2}101¯1¯ type of deformation twinning and the extent of its effect on promoting this type of twinning was observed to be texture dependent. The influence of Sn in promoting twinning was seen to be stronger when the texture of the samples was relatively less favourable for the twinning.

Electrical resistivity behaviors of liquid Pb–Sn binary alloy in the presence of ultrasonic field

Electrical resistivity behaviors of liquid Pb–Sn alloys have been investigated in the presence of ultrasonic field. The process demonstrated significantly that electrical resistivity could reveal the precise influence caused by ultrasound. Details revealed by applying the resistivity measuring approach to the liquid Pb–Sn alloy show that the short ordered structures in the liquid could be modified by ultrasonic irradiation, and the resistivity approach could have application value in the ultrasonic irradiation process on the specific liquid metals and alloys.

A compositional study of Cypriot bronzes dating to the Early Iron Age using portable X-ray fluorescence spectrometry (pXRF)

A collection of 157 copper alloy artefacts from the necropolis of Palaepaphos Skales, located in south-west Cyprus, dating to the 11th-8th centuries BC, was studied and chemically analysed with a handheld pXRF instrument to determine the alloy type that was used for their production. The collection consists of Cu–Sn binary alloys. The relative concentration of the two metals seems to have been determined by the type of artefact the alloy was used to produce. The results also imply that fresh rather than recycled metal was used. The majority of the artefacts are made of a bronze with an average tin content of 8.1 ± 2.2%. There is, however, a group of objects with a characteristic golden surface, under the patina, which was found to have a significantly higher tin concentration, that averages 18.6 ± 2.8% Sn. The lead content in the assemblage ranges from 0.1 to 2.6%. Because lead concentration in local Cypriot ores is unusually low, its presence is interpreted as a deliberate addition even at these low concentrations. The iron content ranges from 0.1 to 1.4%, while zinc is present only in 20 artefacts, exhibiting a concentration range of 0.2–1%. Both elements are believed to be non-intentional additions to the alloys, resulting from the smelting process and originating in the copper ores (which are sulphidic and closely associated with sphalerite). Arsenic is detected in 25 artefacts, in a concentration of 0.2%. The limited amount of arsenic in only a few of the artefacts under study may be the result of the use of polymetallic ores from the area of Limassol Forest, the only Cypriot ores where low amounts of arsenic can be detected, or can be interpreted as evidence for the possible use of recycled metal deriving from artefacts dating to the Early and Middle Bronze Age. The present study provides significant evidence concerning the continuity of the use of bronze with high tin content in the area of Palaepaphos throughout the Early Iron Age.

Measurement of zinc activity in the ternary In–Zn–Sn alloys by EMF method

Activity of zinc in liquid In–Zn–Sn alloys has been measured by electrochemical technique based on molten salt electrolyte galvanic cell in the temperature range 753–853K along three ternary sections of Znx(InySn1−y)1−x where y=0.67, 0.50 and 0.33. The activity of indium in In–Sn binary alloys has also been measured by the same technique in the same temperature range. The activity of Zinc in In–Zn–Sn alloys shows positive deviation from the Raoult's law over entire range of composition. The activity of indium in In–Sn alloys shows negative deviations from ideality for entire composition. The excess molar free energies have been computed by the Darken's treatment of the ternary solutions using In–Sn binary data and ternary data in this study. Isoactivity curves at 813K in the ternary In–Zn–Sn alloys were derived by combining the activity data of In–Zn and Sn–Zn alloys. The values of excess molar free energy in this study are in good agreement with those calculated from the general model calculation proposed by Chou.

ARCHAEOMETALLURGICAL CHARACTERIZATION OF HELLENISTIC METAL OBJECTS: THE CONTRIBUTION OF THE BRONZE OBJECTS FROM RISHON LE‐ZION (ISRAEL)*

An archaeometallurgical analysis is presented of 14 bronze artefacts retrieved from an Early Hellenistic–period farmstead in controlled archaeological excavations at Rishon Le‐Zion, Israel, and dated to the first quarter of the third century bce according to coins and pottery vessels. The bronze assemblage includes a needle, pins, spatulas and fibulas. The aims of the research are to determine the composition, microstructure and manufacturing process of these artefacts, and to discover their place of production. This will provide a better understanding of Hellenistic technological abilities and material culture. The examination included optical microscopy, microhardness, SEM including EDS, and XRD. The results show that the collection consists of Cu–Sn binary alloys, with evidence for a controlled alloying process and the absence of recycling. Furthermore, the microstructure of the objects indicates that all artefacts were produced by a cold‐working process. Moreover, the manufacturing process of the rectangular cross‐section fibulas included sophisticated joining techniques of copper and iron.

Effect of traveling magnetic field on dendrite growth of Pb-Sn alloy during directional solidification

The influence of melt convection on dendrite growth during the upward-directional solidification of Pb-33%Sn binary alloys was investigated. The melt convection was modulated by traveling magnetic field. When the direction of traveling magnetic field was changed from upward to downward, the primary dendrite spacing gradually increased, and the distribution peak of the primary dendrite spacing shifted to the field of narrower spacing. These result from the different intensities of melt convection, which are controlled by the traveling magnetic field. The effects of the traveling magnetic field on melt convection are similar to those of adjustment in the gravity level, thus, the primary dendrite spacing varies. When the intensity of the traveling magnetic field was 1 mT, and the drawing speed was 50 μm/s, the gravity acceleration reached 0.22 g for the downward-traveling magnetic field and 3.07 g for the upward-traveling magnetic field.

A generalized computational interface for combined thermodynamic and kinetic modeling

The computational interface developed by Huang et al. (2008) [Z. Huang, P.P. Conway, R.C. Thomson, A.T. Dinsdale, J.A.J. Robinson, CALPHAD 32 (2008) 129–134] has been extended and generalized in different programming and modeling environments, which includes C, Fortran, Python and Java besides MATLAB and COMSOL Multiphysics. The generalized computational interface can be used to integrate various software packages for materials and process modeling into one programming platform, within which complicated modeling processes beyond the capability of these software packages can be achieved, such as combined thermodynamic and kinetic modeling, microstructural morphology evolution modeling for systems with arbitrary geometries and microstructure-based property prediction. The interface is applicable to all software packages that provide a dynamic-link library or DLL and the incorporation of Thermo-Calc and MTDATA are introduced in this paper. Several application examples utilizing the thermodynamic data of a Cu–Sn binary alloy system and an Fe–Cr–C ternary system are presented. In addition, modeling of solidification, using both a phase field and a phase field crystal models with the finite element method, are conducted within the integrated platform.

Partial and integral enthalpies of mixing of Ag–Ga–Sn liquid alloys

A Calvet type calorimeter was used for measurement of partial and integral enthalpies of mixing of Ag–Ga–Sn alloys. The Ag–Ga binary alloys have been studied with 0 < x Ag < 0.79 composition and in the 803–1073 K temperature range. The mixing enthalpies at 803 K of Ga–Sn binary alloys have been determined for x Sn < 0.35. The Ag–Ga–Sn ternary liquid alloys have been investigated at 803 K along the following sections: x Ag/ x Ga = 1/3, x Ag/ x Ga = 0.36/0.64, x Ag/ x Ga = 1/1, x Ga/ x Sn = 1/3, x Ga/ x Sn = 1/1, x Ga/ x Sn = 0.65/0.35 and x Ga/ x Sn = 3/1. Experimental data were used to obtain the binary interaction parameters by using the Redlich–Kister polynomial for the Ag–Ga binary system, while the Redlich–Kister–Muggianu method was used to determine the ternary interaction parameters for the Ag–Ga–Sn system. The experimental values and the fitted curves were compared with those predicted from the Muggianu and Toop methods.

Formation of the solidified microstructure in Mg–Sn binary alloy

The solidified microstructures in Mg–3Sn and Mg–5Sn (wt%) alloys were investigated experimentally. For Mg–3Sn, secondary and ternary dendrite arms grow rapidly from α-Mg equiaxed dendrites in a certain direction. When Sn content is increased to 5%, developed secondary and ternary dendrite arms in the upstream direction in the center of the sample do not occur. Formation of this microstructure characteristic was discussed in terms of cooling rate, force caused by fluid flow, and dendrite growth behavior of Mg–Sn alloy. The model for growth restriction factor (GRF) has been further discussed by considering the growth behavior of a dendrite tip, which reveals the relationship between GRF and dendrite growth rate. The relationship between GRF and constitutional undercooling was discussed during dendrite growth. The deviation of growth direction from <1 0 1¯ 0> crystal direction has been analyzed by fluid flow during solidification.