Sn Zn Research Articles

A review on electromagnetic shielding magnesium alloys

Electromagnetic waves generated by electronic equipment are widely present in all living and working spaces because of the rapid development of electronic products and frequent use of digital systems. Electromagnetic shielding is an effective method of protection against these waves. Therefore, the demand for materials with high electromagnetic shielding properties has remarkably increased. Magnesium (Mg) alloys, as potential electromagnetic shielding materials, have sparked great interest worldwide. This review highlights the effects of grain size, texture, alloying elements and second phase on the shielding properties of Mg alloys. Recent progress on the shielding properties of Mg–Zn, Mg–Al, Mg–RE and other new shielding Mg alloys is then summarised, and the successful design of Mg alloys with superior electromagnetic shielding properties, such as Mg–Zn–Y–Ce–Zr, Mg–Sn–Zn–Ca–Ce, Mg–Gd–Y–Zn–Zr and Mg-based composite materials, is described. Finally, this review provides insights into the future development and applications of Mg alloys with superior shielding properties.

Effects of stannum (Sn) addition on corrosion behavior and biocompatibility in vitro of biodegradable Zn–Sn alloys

AbstractZinc (Zn) and its alloys, as novel biodegradable metals, hold great potential in bone implant and metallic stents. Stannum (Sn), an essential trace element, plays an important role in maintaining life activities. Herein, Sn is selected as an alloying element to be added into the Zn matrix to explore the possibility of Zn–Sn alloy as a biodegradable metal for clinical application. This article systemically studies the effects of Sn content on microstructural, electrochemical behavior, corrosion rate, and in vitro biocompatibility of Zn–Sn alloys. Results indicate that the Sn‐rich phase is the main form of Sn in the as‐extruded alloys, and the solid solubility is in an extremely minute quantity. The corrosion of Zn–Sn alloys in conventional simulated body fluid (c‐SBF) solution shows apparent electrochemical characteristics, and Sn‐rich phases are corroded preferably. The corrosion rates of Zn–1.0Sn and Zn–2.0Sn are under 0.2 mm year−1, which can satisfy the requirement of biodegradable medical materials. In addition, Zn–1.0Sn exhibits much better cytocompatibility and hemocompatibility than Zn–2.0Sn. Therefore, Zn–Sn alloy shows great potential applications in the biological field and can be further studied and developed.

Microstructure Analysis and Bulk Texture Study in Wide Magnesium Alloy Sheets Processed by Twin-Roll Casting

The wide magnesium (Mg) alloy sheets produced by twin-roll casting (TRC) are prone to have an inhomogeneous microstructure and basal texture. Texture has a significant effect on the properties of Mg alloy sheets for the processes after TRC, which can be greatly modified by alloy composition. However, systematic studies on the bulk texture of TRCed Mg alloy sheets using neutron diffraction are lacking. In this study, neutron diffraction was used to explore the bulk textures in different positions of the Mg, Mg–Al–Zn, and Mg–Al–Sn–Zn alloy sheets produced by TRC, besides microstructure and micro-texture analysis using field emission scanning electron microscopy and electron backscattering diffraction. The influence of alloy composition on the microstructure and texture evolution of TRCed Mg alloy sheets is explored and discussed. The TRCed pure Mg sheet possesses a relatively strong basal texture, and the texture distribution is inhomogeneous; while TRCed Mg–Al–Sn–Zn alloy sheets feature much weaker textures and a relatively homogenous distribution in different positions. The present study provides guidance for the control of texture via tailoring alloy compositions, which provides candidate Mg alloys suitable for the TRC process.

The mineralization potential of the I-type granites from Misajé pluton (NW-Cameroon): AMS and geochemical constraints

The I-type Pan-African Misajé granites, situated in the Western domain of the Central African Fold Belt are among the late-to post tectonic granites that intruded the ante-Pan-African country rocks. In this study, magnetic susceptibility and geochemistry data are integrated to evaluate the productive and non-productive metal potential of these I-type plutonic granites, which comprise Leucocratic granite, Biotite granite, Biotite-hornblende granite, and granodiorites. The magnetic susceptibility of the representative rock samples of the Misajé pluton ranges from 0.001 × 10−3 SI to 33.2 × 10−3 SI. These values indicate the coexistence of both magnetite and ilmenite-series. The magnetite-series (>3 × 10−3 SI; oxidized type) constitute about 32 vol.% while the ilmenite-series (<3 × 10−3 SI; reduced type) represent 68 vol.%. These magnetite-series vary from small MD (Ms ≤ 1) to coarse PSD (Ms > 1) grains sizes. The Misajé plutonics are high potentially productive in Zn, Th, ilmenite, and magnetite and low productive in Sn, W and Cu though their extension remains limited, probably due to the remobilization of the ancient Paleoproterozoic crust that would have contributed to the dispersing of pre-Pan-African metal deposits.

Novel Mg–Al–Sn–Zn–Y Alloys with Enhanced Strength−Ductility Combination Prepared by Hard‐Plate Rolling

Herein, novel high‐performance Mg–Al–Sn–Zn–Y (ATZ821−xY) alloys are developed via hard‐plate rolling (HPR). With the addition of Y, the heterogeneous grain structure of the HPRed ATZ821 alloy evolves to be more uniform, accompanied with significant weakening in basal texture. This is due to the faster dynamic recrystallization (DRX) induced by the particle‐stimulated nucleation (PSN) effect from the Al2Y particles, pinning effect from well‐dispersed submicrometer‐sized precipitates including Mg17Al12 and Mg2Sn, and the &lt;c + a&gt; slips activated by Y atoms in α‐Mg. Correspondingly, the HPRed ATZ821−1.0Y alloy shows a good combination of strength and ductility, that is, a yield strength (YS) of ≈248 MPa, an ultimate tensile strength (UTS) of ≈385 MPa, and a uniform elongation (UE) of ≈20%. The high YS is mainly due to grain boundary strengthening, which accounts for ≈70% of the total YS. The high UE is mainly attributed to the strong work hardening associated with weakened basal texture, well‐dispersed Mg17Al12 and Mg2Sn precipitates, as well as enhanced &lt;c + a&gt; slips induced by Y atoms in the solid solution.

Influence of annealing temperature on the optoelectronic properties of ITZO thin films

In this work, the electrical conductivity and optical transparency of the In–Sn–Zn–O (ITZO) films annealed at different temperatures were investigated. The results show that the ITZO films transformed from amorphous phase to crystalline phase after annealed in the air. The transmittance of the films improves significantly and all exceed 88%. Meanwhile, the annealed ITZO films exhibit a significant enhancement in conductivity. In particular, ITZO film annealed at 650 °C has high electrical conductivity (∼4.94 × 102 S cm−1) and an excellent figure of merit (∼5.94 × 10−4 Ω−1). Moreover, ITZO thin film transistors were prepared and their performance was tested. After annealing, the high electrical properties of the active layer make the gate regulation ability of the thin film transistors degrade. The annealed films with excellent optoelectronic properties can be applied to transparent electrodes.

Numerical investigation on photon energy absorption parameters for some Bi–Sn–Zn alloys in wide energy region

Numerical investigation on photon energy absorption parameters for some Bi–Sn–Zn alloys in wide energy region

The Formation of the Structure of the Alloys of the Tin–Zinc System upon High-Speed Solidification

The results of the study of the parameters of the structure of the fast-solidificated foil of hypoeutectic, eutectic, and hypereutectic alloys of the Sn–Zn system containing 4.4, 8.8, and 15 wt % Zn are presented. The fast-solidificated foil consists of equiaxial zinc particles and a supersaturated solid solution of tin. The zinc particles are uniformly distributed in the foil, which is induced by the formation of a supercooled and supersaturated liquid solution and its subsequent spinodal decomposition. The tin- and zinc-enriched regions of the liquid solution transform to crystalline phase nuclei. The volume fraction of zinc particles, the mean chord of the random secants on the sections of the zinc particles, and the specific surface of the interphase boundary formed by zinc and tin increase with the increase in the concentration of zinc in the alloys under study. The foil of the Sn–Zn alloys has a microcrystalline structure, in which crystallographic texture of the grains is observed. The formation of the (100) texture of tin and (0001) texture of zinc is observed. The fast-solidificated foils of the alloys are in an unstable state, which leads to the decomposition of the supersaturated solid solution, dissolution of small particles, and growth of large particles. Annealing at 180°C for 22 h induces an increase in the mean chord of the sections of the zinc particles and volume of the zinc particles and a decrease in the specific surface of the interphase boundary.

Investigation of Cu2ZnSnS4 thin film with preannealing process and ZnS buffer layer prepared by magnetron sputtering deposition

Unlike traditional methods for fabricating a CdS buffer layer through chemical bath deposition in thin-film solar cells, this study fabricated a ZnS thin film by sulfurizing the Zn film that was deposited using a magnetron sputtering system at varied temperatures from 500° to 560 °C in a sulfurization furnace. The ZnS thin film have been used as a buffer layer on the Cu2ZnSnS4 absorption layer. In this study, the Cu2ZnSnS4 absorber layer was prepared by first depositing a copper–zinc–tin (CZT) precursor film with a metal stack order of Zn–Sn–Cu–Zn through magnetron sputtering, followed by a preannealing process on the CZT precursor, to promote the interdiffusion of elements for the transfer of the metal phase into the alloy phase. Experimental results revealed the increased crystallite size in the SEM observation, an enhanced Raman intensity at 336 cm−1, and a reduced FWHM value in the XRD study for the Cu2ZnSnS4 thin film fabricated at a sulfurization temperature of 510 °C for 20 min with a preannealing treatment of the CZT precursor at a temperature of 420 °C for 30 min. In addition, the improved optical transmittance to 81.3% and an increased optical band gap value to 3.28 eV due to the reduced grain boundaries was obtained for the ZnS film with improved crystallinity quality fabricated at a sulfurization temperature of 560 °C.

Study on Evaporation Kinetics of Zn in Bi–Zn and Bi–Sn–Zn Systems Under Vacuum Condition

Study on Evaporation Kinetics of Zn in Bi–Zn and Bi–Sn–Zn Systems Under Vacuum Condition

Microstructure, melting behavior and thermal conductivity of the Sn–Zn alloys

Four hypereutectic Sn-Zn alloys with 69.5, 48.3, 28.1 and 14.1 at% of Zn were produced by mixing and melting of pure metals Sn and Zn followed by cooling in air to room temperature. Microstructure and chemical compositions of prepared samples were analyzed by using scanning electron microscopy (SEM) with energy dispersive X-ray spectrometry (EDS). It was found that morphology of primary (Zn) phase changes from rounded and equiaxed dendritic structure to plate-like grains and finally to needle-like shape of grains with decreasing Zn content. Formation of characteristic broken-lamellar type of eutectic microstructure was observed in all investigated alloys. Melting behavior of the alloys was studied using differential scanning calorimetry (DSC). Phase transition temperatures and corresponding heat effects were experimentally determined and compared with the results of thermodynamic and phase equilibria calculations using the CALPHAD (CALculation of PHAse Diagrams) method and optimized thermodynamic parameters from literature. Thermal diffusivity of the studied alloys was measured using xenon flash method in the temperature range from 25 to 150 °C. Based on the measured values of thermal diffusivity and calculated specific heat capacity data, thermal conductivities of the solid alloys were obtained. It was found that thermal conductivity decreases monotonously with increasing temperature and Sn content. The results of thermal conductivity measurements were compared with literature data and with the data obtained from the Wiedemann-Franz law and measured electrical conductivities.

Surface modification of the p-type Cu2ZnSnS4 photocathode with n-type zinc oxide nanorods for photo-driven salt water splitting

The sulfurization of co-sputtering Cu–Zn–Sn metal precursors was employed to prepare the quaternary copper-zinc-tin-sulphide (Cu2ZnSnS4, CZTS) photocathodes on substrates. Influence of [Zn]/[Sn] ratios in CZTS photocathodes on their phases, morphologies, and the efficiencies of photo-driven salt-water splitting was examined. Pristine p-type CZTS photocathodes showed the highest photo-driven performance of 0.61 mA cm−2 in an electrolyte containing 1 M sodium chloride with the external bias kept at −1.0 V vs. Ag/AgCl. An n-type zinc oxide (ZnO) nanorod arrays layer was then coated on the CZTS photocathode to improve its photo-driven salt-water splitting performance. The CZTS/ZnO photoelectrode had the best photo-driven performance of 1.87 mA cm−2 in the 1 M NaCl solution under illumination with the external bias set at −1.0 V vs. Ag/AgCl. From results of electrochemical impedance spectra measurements for the samples in the electrolyte, the CZTS/ZnO sample had good photo-driven salt-water splitting performance due to its lowest charge transfer resistance and p-n junction formed at the sample. Intensity modulated photocurrent spectroscopy and electrochemical impedance spectra results of samples indicated that the surface states at the CZTS/ZnO interface were the recombination centers with the electrons from the CZTS sample and holes from the ZnO and therefore improved its photo-driven salt-water splitting performance.

Experimental investigation and modeling of vapor-liquid equilibria for Bi–Zn and Bi–Sn–Zn systems at 10 Pa

For the Bi–Zn and Bi–Sn–Zn systems, vacuum distillation experiments were carried out at 10 Pa. The results show that the content of Zn for the Bi–Zn system in the vapor phase could reach more than 0.999 mol fraction in vacuum distillation. The VLE (vapor-liquid equilibrium) data were correlated using the Tsuboka-Katayama's modification of the Wilson equation (T-K-Wilson). The correlation showed good agreement with experimental data. Thermodynamic consistency tests of experimental data for the binary and ternary systems were presented by the Van Ness method. The results demonstrate that VLE phase diagram is reliable for predicting the process of vacuum distillation for the systems. It provides an efficient way to guide the separation and purification of crude Zn in vacuum metallurgy

Study on Microstructure and Properties of 12Ag–Cu–Zn–Sn Cadmium-Free Filler Metals with Trace In Addition

The effect of different In contents on the melting characteristics, mechanical properties, and microstructure of 12Ag–Cu–Zn–Sn filler metal was investigated in this paper, and flame brazing of 304 stainless steel and copper plates was done using the 12Ag–Cu–Zn–Sn–xIn filler metal. The results indicate that adding appropriate amount of In can evidently decrease the solidus and liquidus temperatures and improve the wettability of the low silver based filler metals. In addition, the shear strength of 304 stainless steel and copper plates joint brazed by 12Ag–Cu–Zn–Sn–1In are satisfactory due to the solution strength effect, and scanning electron microscopy examination of the braze-zone revealed that more relatively sound joints were obtained when brazing was done with 12Ag–Cu–Zn–Sn–xIn filler metal than with Indium free one; its performance is comparable to that of the joint brazed with the 20Ag–Cu–Zn–Sn filler metal, having a remarkable silver-saving effect.

Porous Sn obtained by selective electrochemical dissolution of melt-spun Zn70Sn30 alloys with lithium and sodium storage properties

Zn70Sn30 alloys were prepared with two markedly different cooling rates of the melt - by conventional casting and by rapid solidification technique (melt spinning). As a result, alloys with different morphology and microstructure were obtained. Additionally, certain extension of the Sn(Zn) solid solution was also observed in the rapidly solidified material. After selective electrochemical dissolution of the as-cast alloys (nano)porous structures based on Sn were formed, as the structures obtained from the melt-spun alloys reveal significantly smaller pores as well as more homogeneous pores distribution on the alloy surface. An important result is also the mechanical stability of the porous structures prepared from melt-spun ribbons, which fact together with the appropriate composition makes them suitable for use as negative electrodes in ion batteries operating on the “alloying” principle. The porous electrodes obtained from the melt-spun Zn70Sn30 alloy deliver relatively high discharge capacities in Li- and Na-ion cells (around 440 and 210mAh/g, respectively). The cycling stability of the porous structures is better in the Na-ion cell. The initial results obtained from testing of Sn-based porous materials as electrodes in Na ion batteries are encouraging and deserve further optimization of the alloys composition, phase composition, microstructure and pores size.

Improving Strength and Electromagnetic Shielding Effectiveness of Mg–Sn–Zn–Ca–Ce Alloy by Sn Addition

The strength and electromagnetic shielding capability are two essential requirements for lightweight metallic materials as shielding materials. However, it is still a challenge to develop magnesium (Mg) alloys with both high strength and favorable electromagnetic shielding capability. Herein, the results show that alloying with Sn in Mg–xSn–Zn–Ca–Ce alloys simultaneously increases both strength and electromagnetic shielding effectiveness (SE). After Sn alloying, the average grain size of the alloys is greatly reduced, whereas the intensity of basal texture is enhanced, and the precipitation of Mg2Sn phase is promoted. The Mg–3Sn–Zn–Ca–Ce alloy attains best comprehensive mechanical properties and electromagnetic SE (ultimate tensile strength (UTS) of 337 MPa and SE of 91–114 dB) in Sn containing alloys. The increase in strength is attributed to the combination of grain refinement, texture strengthening, and precipitation strengthening. The great electromagnetic SE is mainly due to the regularly arranged Mg2Sn precipitates in the basal plane.

Room-Temperature Electron Paramagnetic Resonance Study of a Copper-Related Defect in Cu2ZnSnS4 Colloidal Nanocrystals

We report on electron paramagnetic resonance (EPR) spectroscopy of Cu–Zn–Sn–S (CZTS) nanocrystals (NCs) synthesized by a colloidal chemistry method. The chemical composition of the NCs is character...

Performance assessment of Zn–Sn bimetal oxides for the removal of inorganic arsenic in groundwater

Millions of people worldwide are compelled to consume water with high arsenic levels that affect their health adversely. This point intrigued the researchers to develop an effective and economical solution to reduce the high arsenic level to the safe standard limits. This research focuses on the adsorptive removal of arsenate ions onto a novel bimetal oxide particle prepared by mixing Zn and Sn at different atomic ratios. The fabricated bimetallic oxides were characterised by applying various techniques such as XRD, SEM-EDX, BET and FTIR to comprehend the morphology and physico-chemical properties. Batch adsorption experiments were conducted to monitor the arsenate removal under varying process variables such as pH, dosage, contact time etc. The investigation revealed that Zn/Sn bimetal oxide particles prepared with atomic ratio 2:1 showed maximum arsenate removal efficiency compared to other atomic ratios. The removal was found to be pH, dose and temperature dependent and the highest removal of 98.8% was observed at pH 4 with 0.125 g/L of adsorbent dose with an initial dye concentration of 2.5 ppm at 45 °C. Kinetic study and isotherm study of the sorption experiment showed that the pseudo-second order model and Langmuir isotherm model were best suited for the adsorption of arsenate ion the prepared Zn/Sn bimetal oxide adsorbent. The maximum adsorption capacity of the adsorbent computed as 41.29 mg/g at 318K. A regeneration study revealed that 0.1 M phosphoric acid showed 96% desorption of adsorbate. The practical applicability of the Zn/Sn bimetal oxide was also explored to evaluate the performance in real condition.

Thermodynamic, surface and transport properties of ternary Al–Sn–Zn liquid alloy and its sub binaries

ABSTRACT The excess free energies of sub-binary Al–Sn, Sn–Zn and Zn–Al alloys and ternary Al–Sn–Zn alloy were computed using the optimised exponential parameters of R–K polynomial at 973, 1073, 1173 and 1273 K. The computed values of free energy of mixing, enthalpy of mixing and activity of the ternary alloy were compared with the available experimental data. The surface concentrations of the monomers of the ternary Al–Sn–Zn alloy were computed using Butler model. The surface tension of the ternary liquid alloy was calculated in the framework of Chou, Kohler, Toop and Bulter models using optimised parameters for the excess surface tension. The viscosity of the sub-binary systems have been computed using Kaptay equation with the help of calculated results of enthalpy of mixing, and the viscosity of the ternary alloy were computed in the framework of Chou, Kohler and Toop model using optimised parameter for the excess viscosity.

Nanostructured composite powders for producing protective coatings of machinebuilding parts and units

The paper studies a method for producing nanostructured composite powders of the metal – non-metal system. Powders preparation by universal disintegrator-activator technology, processing in planetary ball mills and bowl grinders is shown on the Al–Zn–Sn composition and titanium nitride nanoparticles. Judging by engineering-and-economical performance, the most promising method for obtaining nanostructured composite powders is the method of processing in a bowl grinder.