Addition Of Sn Research Articles

Effect of Cu, Sn and Sb Addition on the Structural, Thermal and Magnetic Properties of Body-Centered Cubic Structured Conimngasi High Entropy Alloy

Effect of Cu, Sn and Sb Addition on the Structural, Thermal and Magnetic Properties of Body-Centered Cubic Structured Conimngasi High Entropy Alloy

Microstructure and mechanical properties of squeeze cast Mg-Sn/TiO2 composites

The present work investigates the effect of minor addition of Sn on the microstructure and mechanical behavior of Mg- TiO2 composites. The composites were prepared by stir squeeze casting technique under the argon gas inert atmosphere at a squeeze pressure of 100 MPa. Microstructural and morphological observations were investigated using field emission scanning electron microscopy (FESEM) respectively. Microstructural characterization showed homogeneous distribution of TiO2 particles in α-Mg matrix, evidential grain refinement and very minimal porosity. Mechanical properties such as hardness, ultimate compressive strength (UCS), and failure strain rate under compressive loading were estimated. Mechanical test results revealed that the hardness, and compressive properties of Mg- TiO2 composite were significantly improved up to the addition of 10 wt% of TiO2. The significant improvement in mechanical properties could be attributed to the uniform distribution of TiO2 grain refinement and the formation of intermetallic phases.

Improved Tribocorrosion Resistance by Addition of Sn to CrFeCoNi High Entropy Alloy

Among the high entropy or complex concentrated alloys (HEAs/CCAs), one type of system is commonly based on CoCrFeNi, which as an equiatomic quaternary alloy that forms a single phase FCC structure. In this work, the effect of Sn in an equiatomic quinary system with CoCrFeNi is shown to lead to a great improvement in hardness and resistance to tribocorrosion. The addition causes a phase transition from a single FCC phase in CoCrFeNi to dual phase in CoCrFeNiSn with an Ni-Sn intermetallic phase, and a CoCrFeNi FCC phase. The presence of both the hard intermetallic and this ductile phase helps to resist crack propagation, and consequent material removal during wear. In addition, the high polarization resistance of the passive film formed at the surface and the high corrosion potential of the Ni-Sn phase contribute to preventing chloride corrosion attack during corrosion testing. This film is tenacious enough for the effect to persist under tribocorrosion conditions.

Effects of Sn and Sb on the Hot Ductility of Nb+Ti Microalloyed Steels

Referencing the composition of a typical Nb+Ti microalloyed steel (Q345B), two kinds of steels, one microalloyed with Sn and Sb, and the other one only microalloyed with Sb were designed to study the effects of Sn and Sb on the hot ductility of Nb+Ti microalloyed steels. The Gleeble-3500 tester was adopted to determine the high-temperature mechanical properties of the two test steels. Fracture morphologies, microstructures and interior precipitation status were analyzed by SEM, CLSM (Confocal laser scanning microscope) and EDS, respectively. Results revealed that within the range of 950–650 °C, there existed the ductility trough for the two steels, which were mainly attributed to the precipitation of TiN and Nb (C, N). Additionally, precipitation of Sn and Sb were not observed in this research and the hot ductility was not affected by the addition of Sn and Sb, as compared with the Nb+Ti microalloyed steel. Therefore, addition of a small amount of Sn and Sb (≤0.05 wt.%) to the Nb+Ti microalloyed steel is favorable due to the improvement on corrosion resistance.

Wetting of SiC by molten Cu–20Me–2Cr (Me=Ag, Mn, Si, and Sn) alloys at 1373 K

Abstract In this work, the effect of the third addition (Ag, Mn, Si, and Sn) on the wettability and the interfacial structures of Cu–20Me–2Cr/SiC systems was investigated. The third addition Me has the obvious effect on the wettability and the spreading dynamics. The sequence of effectiveness is Sn > Ag > Mn > Si. Si Addition can suppress the precipitation of the wettable reaction products, and thus that caused the poor wettability. Although additions of Ag and Mn can improve the wettability significantly, a dissolution zone beneath the reaction layer would be formed. When the third addition Me was thermodynamically repulsive with Si. Meanwhile, the critical concentration of Si in liquid for equilibrium with SiC was less than the corresponding amount of graphite consumed by Cr addition. The dissolution zone would be suppressed. Sn addition satisfied this situation, and thus the best wettability can be achieved. The spreading of Cu–20Me–2Cr/SiC was controlled by the decomposition of SiC rather than the precipitation reaction.

Low-temperature densification and microstructure of W–Cu composites with Sn additives

Dense and homogeneous W–Cu composites with high strength were successfully prepared from Cu-coated W powders by hot pressure sintering (800 °C) with Sn as activated additives. The relative density, microstructure and properties of W–Cu composites with Sn additives were studied. The results have indicated that the addition of Sn additives could significantly promote the densification of W–Cu composites. When Sn was added as additives, the sintering process is mainly the sintering between Cu–Cu and Cu–Sn, and the better mobility of Cu–Sn solid solution is help to eliminate pores and promote low-temperature densification. The relative density of sintered composites has reached 99.2% with 2 wt.% Sn additives. Stacking faults and Twin structure can be distinctly observed in the Cu matrix when 2 wt.% Sn was added as additives. With adding of Sn additives，the Vickers hardness has increased to 263.5 HV. The addition of Sn can lead to the strengthening of interface bonding of sintered composites, and the fracture microstructure with the ductile fracture of Cu matrix and the trans-granular fracture of W phase has been observed in the sintered composites with Sn additives. The bending strength of sintered composites has increased to 993.1 MPa due to the transform of fracture mechanism of sintered composites. The coefficient of thermal expansion of sintered composites has reduced to the minimum value of 7.56 × 10−6/K with the 1.5 wt.% Sn additives.

Low Young's modulus of cold groove-rolled β Ti–Nb–Sn alloys for orthopedic applications

The effects of composition and cold groove-rolling on Young's modulus were investigated to achieve low Young's modulus in β Ti–Nb–Sn ternary alloys for orthopedic applications, using Ti-(27.5–37.5)%Nb-(2.5–11.25)%Sn ternary alloys. Optical microscopy, transmission electron microscopy, and X-ray diffractometry revealed that the constituent phases of quenched and rolled alloys were classified into three regions of β, β(ω)+α” and α” in the Ti–Nb–Sn ternary phase diagram. The β phase was observed to stabilize by the addition of Sn, and the least stable β alloys existed along a line connecting Ti-37.5Nb-2.5Sn and Ti-27.5Nb–11Sn. Low Young's moduli of approximately 50 GPa were achieved by the least stable, quenched β Ti–Nb–Sn alloys, and these further decreased by cold groove-rolling, reducing the cross section by 75%. The lowest Young's modulus of 36 GPa was realized for the cold groove-rolled Ti–35Nb-3.75Sn alloy, in which the textures of [010]α” of deformation-induced α” martensite and [011]β of the β matrix developed preferentially, parallel to the rolling direction. The lattice deformation strain along the [010]α” axis accompanied by β to α” martensitic transformation was observed to depend on the alloy composition and was maximized in Ti–35Nb-3.75Sn. Thus, the low Young's modulus of the least stable β Ti–Nb–Sn alloys obtained after cold groove-rolling was attributed to the development of [010]α” and [011]β textures along the rolling direction, and the lowest Young's modulus of the cold groove-rolled Ti–35Nb-3.75Sn alloy was due to a large lattice deformation strain along the [010]α” axis accompanied by β to α” transformation.

Effect of Cr and Sn additions on microstructure, mechanical-electrical properties and softening resistance of Cu–Cr–Sn alloy

The effect of micro-alloying elements of Cr and Sn on microstructures, mechanical-electrical properties and softening resistance of the novel Cu–Cr–Sn alloys were investigated in details by transmission electron microscopy (TEM), atom probe tomography (APT), electron backscatter diffraction (EBSD) and X-ray diffraction (XRD). The results showed that the tensile strength, yield strength, microhardness and electrical conductivity of Cu-0.67Cr-0.23Sn alloy by 80% cold-rolling and aging at 400 °C for 2 h can reach 566.3 MPa, 527.6 MPa, 186.2 HV and 73.3 %IACS, respectively. The TEM and APT analysis indicated Sn addition can promote the precipitation of Cr phase and inhibit the coarsening of Cr precipitates, thus improving the strength of Cu–Cr–Sn alloy. The precipitation strengthening was the dominant mechanism for improving the yield strength of Cu–Cr–Sn alloys. Besides, the designed Cu–Cr–Sn alloys exhibited a high softening temperature since the addition of Sn inhibited the coarsening of Cr precipitates and delayed the recrystallization of deformed structure.

Effect of Sn addition on the microstructure and mechanical properties of AZ31 alloys

An Mg-3Al-1Zn-xSn (x = 0, 3, 6, 9) alloy was prepared by die-casting and analyzed by XRD, SEM, and EBSD. The microstructure, second phase, and grain orientation of the AZT31x alloy were characterized. As the Sn content increased from 3 wt.% to 9 wt.%, the tensile and yield strength of the alloy were effectively improved. With the addition of Sn, the grain size of alloys decreases gradually blocking the dislocation by the grain boundary and the dispersion of the Mg2Sn second phase in the AZT31x(x = 3, 6, 9) alloys contributes to the strength via grain boundary pinning. According to theoretical analysis and calculation, the high strength of AZT319 alloy is partly attributed to the grain fine strengthening ) and second phase strengthening The total increased strengthening value is lower than experimental value (). The ratio about / and / in die-cast alloys tensioned to 0.08 deformation gradually decrease, which can reflect that high-Sn content contributes to the strain hardening behavior. The ductility of AZT313 alloy was lightly improved due to the {10-12} tensile twins. When excessive Sn was added, the Mg2Sn second phase coarsened and acted as the nucleus of micro-cracks during the stretching process, thereby reducing the ductility of the alloy.

Effect of Alloying Elements on Pit Growth in AA7075

AA7075 is known to a show high strength/weight ratio but suffers from localized corrosion, such as filiform corrosion, pitting, crevice corrosion, and stress corrosion cracking in Cl-containing environments. It has been proposed that Cu-containing intermetallics deteriorate the corrosion resistance and are the initiation sites of pitting. When AA7075 is immersed in an aqueous solution containing NaCl, the intermetallic compounds dissolve, and Cu-enriched particles are formed on and around the intermetallic compounds. Then, the Cu-enriched particles act as a cathode for the oxygen reduction and hydrogen generation reactions, and a strong alkali is locally generated. As a result, it is considered that the Al matrix dissolves, and local corrosion occurs. Therefore, alloy elements that suppress the cathode reaction on the Cu-enriched particles were studied.The samples were prepared from the arc-melting of AA7075 and pure Sn. The concentration of Sn was changed from 0.1 to 5 mass%. After casting, the ingots were heated to 430°C and rolled to a thickness of 2 mm. A solution treatment was performed at 500°C for 2 h. After the heat-treatment, the sample surfaces were polished with a diamond paste down to 0.25 µm.In order to characterize the shape and distribution of the intermetallic particles in the samples, the sample surfaces were observed with an optical microscope and SEM-EDS. The open circuit potentials of AA7075 were measured in 0.1 M NaCl adjusted to pH 6.0 for 16 h. The area exposed to the electrolyte was 10 mm × 10 mm. The measurements were performed in a naturally aerated solution, and Ag/AgCl (3.33 M KCl) was used as a reference electrode. After immersion, the sample surfaces were inspected. Anodic polarization curves of AA7075 were measured in 0.1 M NaCl adjusted to pH 6.0. The measurements were performed in the aerated solution, and the electrode area was 10 mm × 10 mm. In addition, that of pure Sn was also measured. The number of intermetallic compounds in AA7075 with 0.1 mass% Sn was low compared with AA7075. In the initial stage of immersion of AA7075 and Sn-added AA7075, the open circuit potentials were located approximately – 1.0 V and increased with time. Finally, the potential reached around – 0.7 V. The lower potential duration was prolonged by the Sn addition. After immersion, filiform-like corrosion and pitting were observed on the samples. In addition, the Al-matrix and the intermetallic compounds discolored by dissolution. The pitting potential of AA7075 and the 0.1 mass% Sn-added AA7075 alloy was -0.65 V, and no difference was observed.

Study of aging stability and precipitation kinetic of the Al–Zn–Mg alloy applied for auto body structures

The aging stability and influence of Sn addition on precipitation kinetic were fully investigated for a novel Al–Zn–Mg aluminum alloy used for auto body structures. Microstructure evolution was characterized using Differential Scanning Calorimetry (DSC) analysis, Transmission Electron Microscopy (TEM and HRTEM), and Selected Area Electron Diffraction (SAED) techniques. Micro-hardness under different evolution was studied accordingly. Our results indicated that, the bake hardening ability was strongly improved by forming GPⅡ zone under the pre-aging treatment at 120 °C + 20 min，which is completely coherent with the matrix and has strong thermal stability. It was particularly found that the coupling of pre-aging process and Sn addition reduce the precipitation activation energy of the η′ phase from 95.38 kJ/mol in the natural aging state to 38.2 kJ/mol in the Sn-containing pre-aging state, which obviously enhances the bake hardening response.

On the Microstructure and Properties of Nb-18Si-6Mo-5Al-5Cr-2.5W-1Hf Nb-Silicide Based Alloys with Ge, Sn and Ti Additions (at.%).

We studied the microstructures and isothermal oxidation of the Nb-silicide-based alloys Nb-11.5Ti-18Si-5Mo-2W-4.9Sn-4.6Ge-4.5Cr-4.7Al-1Hf (JZ4) and Nb-21Ti-18Si-6.7Mo-1.2W-4.4Sn-4.2Ge-4Cr-3.7Al-0.8Hf (JZ5), calculated their average creep rate for the creep goal conditions of T = 1200 °C and σ = 170 MPa, and compared properties of the two alloys with those of other refractory metal (RM) complex concentrated alloys (RCCAs). Both alloys had a density less than 7.3 g/cm3 and lower than the density of multiphase bcc solid solution + M5Si3 silicide RCCAs. There was macrosegregation of Si in both alloys, which had the same phases in their as-cast microstructures, namely βNb5Si3, αNb5Si3, A15-Nb3X (X = Al, Ge, Si, Sn), TM5Sn2X (X = Al, Ge, Si), C14-Cr2Nb, but no solid solution. After heat treatment at 1500 °C for 100 h, a low volume fraction of a W-rich (Nb, W)ss solid solution was observed in both alloys together with βNb5Si3, αNb5Si3 and A15-Nb3X but not the TM5Sn2X, whereas the Laves phase was observed only in JZ4. At 800 °C, both alloys did not pest, and there was no spallation of their scales at 1200 °C. At both temperatures, both alloys followed parabolic oxidation kinetics and their weight changes were lower than those of Ti-rich Nb-silicide-based alloys. The oxidation of both alloys was superior to that of other RCCAs studied to date. For each alloy the Si macrosegregation, volume fraction of solid solution, chemical composition of solid solution and Nb5Si3, and weight changes in isothermal oxidation at 800 and 1200 °C that were calculated using the alloy design methodology NICE agreed well with the experimental results.

Influence of strain rate and Sn in solid solution on the grain refinement and crystalline defect density in severely deformed Cu

A commercially pure Cu and a Cu-8 wt.%Sn alloy were subjected to high pressure torsion (HPT) to study the effect of Sn as solute element and deformation rate on the grain refinement mechanism and the defect accumulation in Cu. The microstructure and hardness of produced ultrafine grained (UFG) states of both materials were carefully characterized. We show that addition of Sn in Cu leads to significant decrease in grain size, accumulation of higher stored energy and increase in hardness accompanied with the delay of hardness saturation with shear strain. Increasing HPT deformation rate induces significant heat dissipation in the processed materials markedly pronounced in CuSn8 as compared to Cu. Surprisingly, deformation rate has the opposite effect on the microhardness of UFG Cu and CuSn8, which decreases with the deformation rate for the case of Cu, while exhibits faster saturation to higher values for CuSn8. We also show that despite higher self-heating at higher deformation rates, higher HPT rotation speed provides reduction in grain size and increase in the defect density for CuSn8 alloy. This effect is assumed to be related to strong interactions between Sn solute atoms and strain-induced defects so that mechanically driven effects prevail over dynamic annihilation of dislocations. Finally, we present a qualitative model based on the phenomena of production and annihilation of dislocations. This model was able to reproduce the evolution of grain size, concentrations defects and hardness with different deformation parameters and after the addition of solute element in material.

The Augmentation of Photocatalytic Efficiency Due to the Transition Effect Between Spherical Shape and Rod-Like Structure of Sn Levels in ZnO Nanoparticles

Polymer assisted without and with Sn in Zinc Oxide nanoparticles were synthesized by shallow chemical precipitation method by variable weight percentages (0, 10, 20, and 30wt %) of Sn in the poly-vinyl-pyrrolidone surfactant medium. The change in Sn levels in ZnO led to creating a change in morphology. The morphology was changed from boiled broken rice structure to rod-like structure. At the same time, the agglomeration level of this structure got increased at the first level of Sn addition in ZnO itself. Further addition of Sn level in the ZnO changed the shapes into a rod like form with a higher rate of agglomeration. The formations of two phases were observed such as ZnO with hexagonal phase and SnO2 with tetragonal phase due to the increase of Sn concentration. The average particle size was increased from 21 to 35 nm due to addition of Sn concentration in the samples. A decrease of bandgap energy from 3.42 to 3.17 eV was noticed from DRS spectra. The existence of Zn, Sn, O and C level was deep-rooted from EDAX spectra. It confirmed that the presence of C was in all samples due to the effect of the polymer surfactant. The photocatalytic activity of the without and with Sn addition in ZnO nanoparticles as catalyst was tested under UV–Visible irradiation. The increase in degradation efficacy was observed due to an increase in Sn levels.

Electrochemical Deposition of PdBiSn Catalyst for Glycerol Oxidation in Alkaline Medium

AbstractPdBiSn thin film on Au substrate was prepared by means of the electrochemical atomic layer deposition (E‐ALD) technique. The morphology and elemental distribution of the catalysts was determined using scanning electron microscope equipped with energy dispersive spectroscopy (EDS) detector. The catalysts contained all the deposited elements distributed evenly on the surface. Electro‐oxidation of glycerol was tested in alkaline media using cyclic voltammetry (CV) and chronoamperometry (CA). The activity of the catalysts towards the oxidation of glycerol improved with the addition of Sn and Bi with the binary PdBi catalyst being the most improved.

The pronounced effect of Sn on RhSn catalysts for propane dehydrogenation

The pronounced effect of Sn on RhSn/γ-Al2O3 catalysts for propane dehydrogenation (PDH) is studied. A 0.5- wt% Rh/γ-Al2O3 catalyst (Rh(0.5)) without Sn exhibits very low propane (C3) conversion (10.7%) and low selectivity (25.4%) for propylene (C3=) at 600 °C and a WHSV of 10.8 h−1. However, the Sn addition to Rh(0.5) increases both the C3 conversion and the C3= yield. Finally, the Rh(0.5)Sn(3.0) catalyst achieves a C3 conversion of 30.8% and a C3= selectivity of 96.3%. It has been reported that PtSn catalysts show an optimized C3= at the Sn/Pt molar ratio of about 1.0, increasing the propene selectivity at the expense of catalytic activity. This is not the case for the RhSn system. The primary product of Rh(0.5) is methane (65%) at the initial time and severe coke formation covers the exposed Rh metal, resulting in low C3 conversion. Both the C3 conversion and the C3= yield increase with increasing Sn content. The low C3 conversion and C3= yield of Rh(0.5) are ascribed to cracking via the strong adsorption of intermediates during propane dehydrogenation, resulting in severe coke formation. The main role of Sn on Rh(0.5) in propane dehydrogenation is to suppress cracking of strongly adsorbed intermediates during dehydrogenation; the gain in C3= selectivity outweighs the loss of activity for propane dehydrogenation to propylene up to a high Sn addition of 3 wt%.

Microstructural evolution, mechanical properties and corrosion behavior of as-cast Mg-5Li-3Al-2Zn alloy with different Sn and Y addition

Influences of Sn and Y on the microstructure, mechanical properties, and corrosion behavior of as-cast Mg-5Li-3Al-2Zn (LAZ532) alloy were investigated. The addition of Sn and Y refines grains and results in the formation of Mg2Sn and Al2Y phases, thus improving the mechanical properties of alloy by second phase strengthening and grain refinement strengthening. As-cast LAZ532 alloy shows typical filiform corrosion morphology, and the addition of Sn and Y does not change the corrosion mode of alloy. As-cast LAZ532−0.8Sn-1.2Y alloy shows excellent mechanical properties with yield strength of 166.2 MPa, ultimate tensile strength of 228.6 MPa and elongation of 14.8 %, and exhibits the best corrosion resistance with the smallest corrosion current density and the lowest anodic dissolution rate.

Effect of Sn Addition on Phase Transformation Behavior of Equiatomic Ni-Ti Shape Memory Alloy

Sn effect on the phase transformation behavior, microstructure, and micro hardness of equiatomic Ni-Ti shape memory alloy was studied. NiTi and NiTiSn alloys were produced using vacuum induction melting process with alloys composition (50% at. Ni, 50% at.Ti) and (Ni 48% at., Ti 50% at., Sn 2% at.). The characteristics of both alloys were investigated by utilizing Differential Scanning Calorimetry, X- ray Diffraction Analysis, Scanning Electron Microscope, optical microscope and vicker's micro hardness test. The results showed that adding Sn element leads to decrease the phase transformation temperatures evidently. Both alloy samples contain NiTi matrix phase and Ti2Ni secondary phase, but the Ti2Ni phase content decreases with Sn addition and this is one of the reasons that leads to decrease the micro hardness of alloy with adding Sn element in a noticeable manner. The micro hardness decreases from 238.74 for NiTi equiatomic alloy to 202 for NiTiSn alloy after heat treatment.

Catalytic conversion of glucose in fructose utilizing high-silica zeolite Sn-ZSM-12

Abstract Tin incorporation in high-silica ZSM-12 zeolite was evaluated using different concentrations of tin and different structure-directing agents (SDA), in order to be used in the glucose isomerization reaction in fructose. The tetraethylammonium hydroxide SDA successfully formed the structure of the high silica zeolite ZSM-12; however, in this system, the addition of Sn prevented the formation of the ZSM-12 zeolite. Therefore, tetraethylammonium bromide was used as SDA, but the syntheses of high-silica ZSM-12 zeolite without and with tin incorporation were not effective. Then methyltriethylammonium chloride was used as SDA, and the high-silica ZSM-12 structure was formed only with the incorporation of tin. The samples with ZSM-12 structure and different concentrations of tin were evaluated in reaction of glucose conversion to fructose. It was found that the sample with the lowest tin content ( Sn / Si = 0 . 005 ) achieved the highest glucose conversion and the highest fructose yield.

Effect of Tin Addition on Shape Memory Effect and Mechanical Properties of Cu-Al-Ni Shape Memory Alloy

This study examines the effect of Sn additions on Cu-14%Al-4.5%Ni shape memory alloy. Sn was added in three different percentages (0.3,1,3) %. The alloys were mechanically tested both in compression test and micro hardness test. Also, a thermo-mechanical test was performed on the alloys. Results showed an increase in the transformation temperature outside the domain and also a better recovery strain with the increase of Sn percentage of 3% Sn addition showed the best results in mechanical properties while the 3% Sn showed a better Shape Memory Properties near to super elastic.