Increasing Bi Content Research Articles

Effect of Trace Bismuth on Deformation Behavior of Ultrahigh-Purity Copper during Hot Compression

The effect of trace Bi impurities on the flow stress, microstructure evolution, and dynamic recrystallization (DRX) of the ultrahigh-purity copper was systematically investigated by a hot compression test at 600 °C. The results show that the peak stress of the ultrahigh-purity copper gradually decreases with increasing Bi content. Trace Bi impurities can refine the microstructure of ultrahigh-purity copper. However, the refinement effect of 50 wt ppm Bi is much more significant than that of 140 wt ppm Bi during the hot deformation. This effect is ascribed to the higher concentration of Bi at GBs, which induces severe GB cracks that reduces the driving force for the nucleation of DRX grains. In addition, the introduction of Bi inhibits the DRX of the ultrahigh-purity copper and transforms its DRX process from the discontinuous dynamic recrystallization (DDRX) to the coexistence of DDRX and continuous dynamic recrystallization (CDRX) mechanisms.

A good balance between the efficiency of ionizing radiation shielding and mechanical performance of various tin-based alloys: Comparative analysis

The Sn-Bix (x = 30, 40, 50, 60 and 70%) radiation shielding alloys were prepared using a melting process of the alloying material in a ceramic crucible at 200 °C for 120 min. The structural characterization for synthesized samples was carried out using X-ray Diffraction technique (XRD). The hardness and elastic properties of the prepared alloys was measured using micro-indentation creep technology and tensile test machine respectively. XRD pattern indicated that that the crystal size of Sn phase is lowered by increasing Bi concentration in the Sn matrix. The hardness decreases as the dwell time increases. The hardness values and elastic properties (in terms of young modulus) were significantly improved due to the decrease in the crystallite size by increasing Bi content. The stress exponent (n) value increase by increasing Bi content which mean that the mechanical properties improved due to increment of resistance. Furthermore, the produced alloys' nuclear shielding ability was investigated. The μm values were calculated using MCNP simulation code and XCOM software over a broad energy range of 0.015 MeV–15 MeV with good agreement between them. Several characteristics are estimated in order to properly understand the researched alloy's radiation and properties of neutron shielding. The findings showed that a higher Bi concentration causes the crystal size to decrease, improving the radiation shielding and mechanical qualities. The alloy Sn-70% Bi has a maximum increase of vicker hardness, tensile strength, and young's modulus. The findings of the shielding parameters indicate that the alloys under study are efficient gamma shielding materials in contrast to other typical shielding materials and materials that have been examined recently. The highest mechanical efficiency and rather strong gamma-ray shielding capabilities are found in the Sn–70Bi alloy. Owing to its ability to effectively balance mechanical performance and shielding, the Sn–70Bi are approved for use in radiation protection. In addition, when compared to all other manufactured alloys, typical neutron shielding materials, and recently investigated materials, the results further demonstrate that the Sn–70Bi alloy has the best neutron attenuation capability. Furthermore, in terms of mass stopping power (MSP) and projected range (PR), the Sn–70Bi alloy demonstrates the most effective attenuation for alpha particles (He+2) and protons (H+1). These results imply that the Sn–70Bi alloy provide superior mechanical performance and nuclear shielding for a range of applications including industrial, medicinal, and nuclear waste storage in the future.

Enhanced gamma-ray shielding capabilities of Bi-Se-Ge chalcogenide glasses: analytical and simulation insights

This study investigates the gamma-ray shielding properties of Bi-Se-Ge chalcogenide glasses using advanced computational tools. The Phy-X/PSD and FLUKA programs were utilized to determine critical shielding parameters such as linear attenuation coefficient ( GLAC ), mass attenuation coefficient ( GMAC ), half-value layer ( GHVL ), mean free path ( GMFP ), and effective atomic number ( Zeff ). Our findings reveal that these glasses exhibit superior shielding capabilities compared to traditional materials. For instance, the GMAC values for the glasses ranged from 101.472 cm2/g to 177.475 cm2/g at a photon energy of 0.015 MeV. Additionally, the GHVL values decreased significantly with increasing Bi content, from 4.082 cm to 3.104 cm at an energy level of 15 MeV. The effective atomic number ( Zeff ) also increased from 36.12 to 53.23 with higher Bi concentrations. These insights, derived from precise computational analysis, highlight the potential of Bi-Se-Ge glasses for applications in radiation protection. The discussion also examines the impact of substituting Bi atoms with Se on the shielding capabilities of the original Bi-Se-Ge glass.Future work will focus on experimental validation of these results to further substantiate our findings.

The role of Bi incorporation on the optical dispersion parameters of binary Se–In chalcogenide glass films as encouraging materials for photovoltaic implementations

The bulk form of Se78In(22-x)Bix (x = 0, 4, 8, and 12 at.%) was produced with melt-quench technology. Subsequently, thin films of these compositions were produced through the thermal evaporation method under vacuum conditions. Analysis via diffraction of X-rays confirmed the disordered character of the resulting films. The refractive index (n) and extinction coefficient (k) were computed using optical transmission T(λ) and reflection R(λ) data. Analysis of optical constants revealed that the optical energy gap Egopt decreases while the Urbach tail Eu augments as the Bi content increases. Other related constants were determined and investigated in relation to variations in Bi content. The outcomes of our study were compared with those published previously. Non-linear parameters were calculated and discussed for the investigated films.

Microstructure evolution and deformation behaviour of Sn-xBi-1Ag Solder alloys: Influences of Bi content

The study of microstructural evolution in ternary Sn–Bi–Ag solder alloys is critical due to its direct impact on the mechanical properties of these low-temperature solder materials. This research compares the solidification and deformation behaviors of two such alloys, Sn–10Bi–1Ag and Sn–57Bi–1Ag, to shed light on the influences of bismuth (Bi) content variations. Experimental results indicate that increasing Bi content alters the solidification process and the degree of undercooling. In the Sn–10Bi–1Ag alloy, the eutectic reaction produces plate-like Ag3Sn with a predominant with {101‾0}hcp facet, considering Ag3Sn as a pseudo-hexagonal structure. Conversely, in the Sn–57Bi–1Ag alloy, Ag3Sn nucleates as the primary phase, exhibiting blocky or extensively branched morphologies, enclosed by various facets including {0001}hcp and {101‾0}hcp. Additionally, two distinct Bi particle sizes were identified in the Sn–10Bi–1Ag alloy: eutectic lamellar Bi (∼200 nm) and Bi precipitates (∼15 nm), when cooled at 10 °C/min, in comparison to typical lamellar β-Sn/Bi eutectics in Sn–57Bi–1Ag. In-situ tensile test revealed that the Sn–10Bi–1Ag demonstrates superior strength and reduced ductility. This is attributed to the reinforcement provided by the smaller-sized Bi particles and the eutectic Ag3Sn structures. In contrast, for the Sn–57Bi–1Ag, the primary Ag3Sn phase tends to fracture during deformation, and the deformation mechanism is predominantly controlled by grain boundary and phase boundary sliding. This study elucidates the significance of Bi precipitates and Ag3Sn in Sn–Bi–Ag solder, providing valuable insights for the alloy design of future low-temperature solders.

Correlation between microhardness and microstructure of low-temperature Sn-xBi-M(Ag, Sb) solders

The correlation between Vickers microhardness and microstructure of low-temperature Sn-xBi-M(Ag, Sb) solders was investigated. The β-Sn grains were refined with increasing Bi content, as well as the additions of Ag and Sb. Fine β-Sn grains in general should strengthen the mechanical properties of solders, however, the Vickers microhardness of Sn-xBi-M(Ag, Sb) solders decreased with increasing Bi content (i.e., fine β-Sn grains). It was shown that the microhardness of Sn-xBi-M(Ag, Sb) solders depended on the amount of Bi/β-Sn interfaces rather than the fine-grain strengthening effect. The smaller the amount of Bi/β-Sn interfaces was, the higher the Vickers microhardness of Sn-xBi-M(Ag, Sb) solders.

Taguchi Optimization of Wetting, Thermal and Mechanical Properties of Sn-1.0wt.%Ag-0.5wt.%Cu Alloys Modified with Bi and Sb.

This study was conducted on SAC105 (Sn-1wt.%Ag-0.5wt.%Cu) lead-free solder modified with Bi and Sb. The wetting, melting point, and mechanical properties were analysed with the addition of 1~5 wt.%Bi and 1~5 wt.%Sb for SAC105 base alloy. The wetting characteristics were assessed by wetting time (zero cross time, ZCT) obtained from wetting balance tests. The mechanical properties were analysed by tensile tests. Considering two factors (Bi, Sb), a three-level (0, 1, 2 wt.%) design of experiment (DOE) method array was applied for Taguchi optimization. The results indicated that the solder wetting increased as Bi content increased, while it decreased with Sb. The ZCT decreased with increasing Bi content up to 4 wt.%, while it increased proportionally to Sb content. The melting point, measured using a differential scanning calorimeter (DSC), showed that the melting point tended to decrease according to Bi increase, while it increases depending on the Sb content. Increase in Bi and Sb levels resulted in enhanced tensile strength in the mechanical properties tests, with Bi having a more noticeable impact. The Taguchi optimized conditions for the Bi and Sb studies were found to be 2 wt.%Bi and 2 wt.%Sb. This led to an optimal set of 0.9 s of wetting time, a 222.55 °C melting point, a 55 MPa tensile strength, and a 50% elongation.

Relationship between disorder, magnetism and band topology in Mn(Sb1–x Bi x )2Te4 single crystals

We investigate the evolution of magnetic properties as well as the content and distribution of Mn for Mn(Sb1−x Bi x )2Te4 single crystals grown by large-temperature-gradient chemical vapor transport method. It is found that the ferromagnetic MnSb2Te4 changes to antiferromagnetism with Bi doping when x ≥ 0.25. Further analysis implies that the occupations of Mn ions at Sb/Bi site MnSb/Bi and Mn site MnMn have a strong influence on the magnetic ground states of these systems. With the decrease of MnMn and increase of MnSb/Bi, the system will favor the ferromagnetic ground state. In addition, the rapid decrease of T C/N with increasing Bi content when x ≤ 0.25 and the insensitivity of T N to x when x > 0.25 suggest that the main magnetic interaction may change from the Ruderman–Kittel–Kasuya–Yosida type at low Bi doping region to the van-Vleck type in high Bi doped samples.

Enhancement of magnetocaloric effect by partial substitution of Bi in La0.60Dy0.10Sr0.30Mn(1−x)BixO3 manganites (x = 0, 0.01, 0.03, and 0.10)

In this study, the effects of Bi substitution for Mn on the magnetic and magnetocaloric properties of La0.60Dy0.10Sr0.30Mn(1−x)BixO3 manganites (x = 0, 0.01, 0.03, and 0.10) synthesized using the sol–gel method ​​were investigated. The samples x = 0, 0.01, and 0.03 had been indexed in an orthorhombic structure (space group Pnma), while sample x = 0.10 had been indexed in a hexagonal structure (space group R3c). The thermomagnetic measurements showed an increase in the Curie temperature (TC) with increasing Bi content, as well as an increase in magnetization at low temperatures. The TC values were determined as 322, 318, 327, and 360 K for x = 0, 0.01, 0.03, and 0.10 samples, respectively. Maximum magnetic entropy change (-ΔSMmax\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-\\Delta {S}_{M}^{max}$$\\end{document}) values ​​obtained from isothermal magnetization measurements showed an increase with the amount of Bi. The -ΔSMmax\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$-\\Delta {S}_{M}^{max}$$\\end{document} value of 3.80 Jkg−1K−1 at 5 T for the x = 0 sample increased to 4.12 Jkg−1K−1 for the x = 0.10 sample with the highest Bi content. From the Arrott curves, it was observed that all samples exhibited a second-order magnetic phase transition. The obtained values of relative cooling power (RCP), which is an important factor in determining the performance of cooling material, are in the range of 282, 262, 251, and 232 Jkg−1 for x = 0, 0.01, 0.03, and 0.10, respectively.

Substantially low thermal conductivity and high thermoelectric figure-of-merit in Bi-doped Sr2CoRuO6 double perovskites

Transition metal oxide thermoelectric materials are interesting due to their high thermal stability, low toxicity, and low cost. Although several interesting thermoelectric oxides have been reported thus far, but reducing the lattice thermal conductivity while maintaining the good electrical conductivity to get optimum thermoelectric performance is still a challenge. In addition, many oxide systems are not well explored as yet for their potential to convert waste heat into electricity using the Seebeck effect. Herein, we report the structural and thermoelectric properties of the Sr2−xBixCoRuO6 (0 ≤ x ≤ 0.8) double perovskites. Rietveld refinement of X-ray powder diffraction data shows that the unit cell parameters increase with Bi content (x). The electrical resistivity decreases with x due to the much larger and well-connected grains in Bi containing samples. The Seebeck coefficient changes its sign from negative to positive with increasing Bi content indicating hole doping. The thermal conductivity of the samples decreases with increasing x due to the soft chemical bonding and heavy atomic mass of the doped Bi atoms. These changes in transport properties lead to a large power factor of 1.87 × 10–4 W/m·K2 and a thermoelectric figure-of-merit of 0.24 for the x = 0.8 sample at 668 K. We estimated the heat capacities from the temperature independent Dulong-Petit limit for solids for calculation of the thermal conductivities and therefore some uncertainty in the reported zT values is expected.

Alloying-Induced Structural Transition in the Promising Thermoelectric Compound CaAgSb.

AMX Zintl compounds, crystallizing in several closely related layered structures, have recently garnered attention due to their exciting thermoelectric properties. In this study, we show that orthorhombic CaAgSb can be alloyed with hexagonal CaAgBi to achieve a solid solution with a structural transformation at x ∼ 0.8. This transition can be seen as a switch from three-dimensional (3D) to two-dimensional (2D) covalent bonding in which the interlayer M-X bond distances expand while the in-plane M-X distances contract. Measurements of the elastic moduli reveal that CaAgSb1-xBix becomes softer with increasing Bi content, with the exception of a steplike 10% stiffening observed at the 3D-to-2D phase transition. Thermoelectric transport measurements reveal promising Hall mobility and a peak zT of 0.47 at 620 K for intrinsic CaAgSb, which is higher than those in previous reports for unmodified CaAgSb. However, alloying with Bi was found to increase the hole concentration beyond the optimal value, effectively lowering the zT. Interestingly, analysis of the thermal conductivity and electrical conductivity suggests that the Bi-rich alloys are low Lorenz-number (L) materials, with estimated values of L well below the nondegenerate limit of L = 1.5 × 10-8 W Ω K-2, in spite of the metallic-like transport properties. A low Lorenz number decouples lattice and electronic thermal conductivities, providing greater flexibility for enhancing thermoelectric properties.

Tunable light emission of Bi and V-doped borosilicate glasses for application in white light-emitting diodes

Melt-quenched borosilicate glasses, co-doped with Bi and V ions, exhibited broad visible spectrum emissions. Bi ions primarily existed as Bi3+, acting as network modifiers, lowering the glass transition temperature linearly with increasing Bi content. V5+ ions adopted tetrahedral coordination as [VO4]3- units. Photoluminescence of Bi ions is shifted from blue to longer wavelengths with higher Bi content, associated with the stabilization of Bi2+ and the presence of Bi3+ in different local environments. Combined with V ions, the glasses emitted light covering the entire visible spectrum, offering the potential for white LED applications with correlated color temperatures ranging from 6135 to 4010 K. The highest QY was 11.9 and 8.0 % upon excitation at 325 and 340 nm.

Advancing humidity sensing and magnetocaloric properties of spinel structural CoCr2O4 nanoparticles achieved via innovative bismuth doping by combustion synthesis

This study explores the influence of Bi-doping on Co1-xBixCr2O4 (x = 0–0.2) nanoparticles synthesized via the solution combustion method, focusing on humidity sensing and magnetocaloric effects. The investigation reveals two magnetic transitions: the Curie temperature (TC) marks the paramagnetic to ferrimagnetic shift, while the spiral transition temperature (TS) indicates a spiral spin order transition. Magnetization measurements demonstrate that −ΔSM and relative cooling power (RCP) values vary with Bi concentration, making these nanoparticles viable for magnetic refrigeration above liquid nitrogen temperatures. Analyzing magnetic entropy variation, the modified Arrott plots and Kouvel-Fisher approach affirm second-order phase transitions. The sensing response exhibits growth alongside relative humidity (RH) and Bi concentration, culminating in an impressive ∼97.56 % sensing response for the 20 % Bi-doped sample. This heightened humidity sensing performance with increased Bi content can be attributed to synergistic effects. These results highlight the potential of 20 % Bi-doped Co1-xBixCr2O4 nanoparticles as promising contenders for enduring and practical humidity sensing applications.

Effect of Alloy Elements on the Performance of Al Sacrificial Anode

Al-Bi-Ga alloy is a good sacrificial anode material, but research on its electrochemical performance in seawater, freshwater, and soil is limited. This article focuses on Al-Bi-Ga-Pb-In and Al-Bi-Ga-Sn-In alloys. The working potential, current efficiency, and corrosion morphology of aluminum alloys under constant current conditions were studied through electrochemical performance testing, microstructure observation, and composition detection. The influence of alloy elements (Bi, Ga, Pb) on the electrochemical performance of aluminum alloys was analyzed. The results indicate that the dissolution morphology of Al-Bi-Ga-Sn-In is better than that of Al-Bi-Ga-Pb-In, and the distribution of Bi element in Al-Bi-Ga-Sn-In is more extensive. The destruction of the oxide film on the surface of aluminum alloy is more uniform, exhibiting better dissolution morphology; As the Bi content increases, the corrosion rate shows a trend of first increasing, then decreasing, and then increasing. The current efficiency first decreases and then increases, usually stopping and rebounding around 4.5%; Ga can increase the corrosion rate and reduce the surface impedance value; When the Ga content is greater than 0.10%, the corrosion rate significantly increases; As the Ga content increases, the current efficiency first decreases and then increases, then stops decreasing and rebounds around 0.2%.

Thermal Stability of Lead-Free Transparent Cloisonné Glazes

Glazes of (70 − x) ZnO-30 B2O3-x Bi2O3 with different Bi2O3 contents were prepared by the conventional melt quench technique. Differential scanning calorimetry (DSC) curves were obtained to determine the glass transition temperature (Tg) and crystallization temperature (Tc) of the glazes. The activation energy of the glass transition (Eg) and crystallization (Ec) were calculated using the Moynihan and Kissinger models, respectively. The glass transition temperature (Tg) decreased linearly with increasing Bi2O3 content. This is because the larger Bi3+ ions reduced network connectivity and opened up the structure. The Tg increased gradually with increasing heating rate (β). This is because the higher heating rate provided more energy for the glass to transition to the liquid state. The activation energy of the glass transition (Eg) decreased with increasing Bi2O3 content. This indicates that the glass-forming ability of the system increased with increasing Bi2O3 content. The energy corresponding to the amorphous-to-crystalline transformation during nucleation and crystal growth (Ec) increased with increasing Bi content to about 30%, and then decreased above 40%. This suggests that higher Ec values have an advantage in preventing crystallization in the crystallization danger region. It can be seen that the addition of Bi2O3 in (70 − x) ZnO-30 B2O3-x Bi2O3 glazes affects the density and distribution of oxygen atoms in the glass structure. It can also be seen that the increased Bi content promotes the formation of Bi-O-Bi bonds, which act as network modifiers to reduce the number of non-cross-linked oxygen atoms and increase network connectivity.

Raman scattering study of photoexcited plasma in GaAsBi/GaAs heterostructures: Influence of carrier confinement on photoluminescence

GaAsBi alloys are potential candidates for near-infrared optoelectronic applications, such as light-emitting diodes, laser diodes, avalanche photodiodes, and solar cells. In this paper, photoexcited plasma in GaAs1-xBix/GaAs (1.7 ≤ x ≤ 8.6%) heterostructures grown by molecular beam epitaxy was investigated using Raman spectroscopy. The strong LO phonon-plasmon coupled mode (LOPC) was generated by continuous-wave laser excitation at room temperature. The upper branch of the LOPC mode (L+ mode) was clearly observed for Bi contents from x = 3.9–8.6%, which indicates that photoexcited carriers with relatively good carrier mobility were confined in the GaAsBi/GaAs heterostructure. The photoexcited carrier density that was obtained by line shape analysis of the Raman spectra based on a dielectric model increased as the Bi content increased from 1.7 to 6.4%. This indicates that carrier overflow from the GaAsBi layer was suppressed because of the larger conduction band offset at the GaAsBi/GaAs heterointerface. In addition, the optical mobility calculated using the damping constant of the photoexcited L+ mode gradually decreased with increasing Bi content. This may be attributed to an increased defect density with decreasing growth temperature. Our findings provide valuable insight into the development of high-performance optoelectronic devices based on GaAsBi alloys and show the potential of Raman spectroscopy for evaluation of carrier confinement in heterostructures.

Intervalley energy separation in the conduction band of InAs1−x Bi x determined by terahertz emission spectroscopy

InAsBi layers with different bismuth content were grown on InAs substrates by solid source MBE. The amount of bismuth incorporated in the layers was estimated using X-ray diffraction measurements. The relaxation degree of the grown crystalline layers was evaluated using reciprocal space map analysis. The intervalley energy separation in the conduction band of InAsBi was studied by Terahertz Excitation Spectroscopy. It has been found that this separation slightly decreases with increasing Bi content. In the studied samples with Bi content varying from 2.7% to 4.5% the Γ-L separation shifts down to about 0.9 eV.

Interfacial Microstructure and Shear Strength Improvements of Babbitt–Steel Bimetal Composites Using Sn–Bi Interlayer via Liquid–Solid Casting

To enhance the performance of Babbitt–steel bimetallic composites, bismuth (Bi) was incorporated into the Tin (Sn)-interlayer. Babbitt–steel bimetallic composites were created using the liquid–solid compound casting method in this study. Sn–Bi interlayer alloys with varying levels of Bi (1, 2, 3, and 4 wt.%) were created. The Babbitt-steel bimetallic composite’s bonding strength and interfacial microstructure were examined in relation to Sn-Bi interlayer alloys. The structure of the interface layer at the Babbitt–steel interface’s edge and center are significantly altered when Bi is added to the Sn interlayer. The relatively higher cooling rate near the edge led to the formation of clear unsolved Sn/Sn–Bi interlayers. Otherwise, the Sn–Bi interlayers in the middle were completely dissolved. By increasing the amount of Bi in the Sn–Bi interlayer alloy, the interfacial hardness of Babbitt-steel bimetallic composites increases by increasing Bi content in Sn–Bi interlayer alloy. Babbitt-steel bimetal composites’ shear strength increased to 28.27 MPa by adding Bi to the Sn interlayer using 1 wt.% alloying, with a 10.3% increase when compared with the reference pure Sn interlayer. Future research that aims to improve the production of Babbitt-steel bimetallic composites with high-quality and long-lasting bi-metal bonding ought to take into consideration the ideal pouring temperature, the preheating of the mold, and the addition of a minor amount of Bi (Bi ≤ 1) to the Sn-interlayer.

Study on the preparation and properties of Sn-0.7Cu-xBi alloy.

This study investigated the impact of different bismuth (Bi) contents on the mechanical properties, melting point, and corrosion resistance of tin-copper (Sn-Cu) series alloys (Sn-0.7Cu). Furthermore, Sn-0.7Cu-xBi alloys with different Bi contents (x = 0, 3, 6, 9, 12, 15 wt%) were prepared through a traditional casting process. The composition and microstructure of the alloy were characterized via X-ray diffraction (XRD) and Scanning electron microscopy (SEM). The impact of Bi on the mechanical properties, melting point, and corrosion resistance of Sn-0.7Cu alloy was analyzed, reaching a peak at 12 wt% Bi. Furthermore, beyond this concentration, the mechanical properties of the alloy exhibited a decline. The corrosion resistance of Sn-0.7Cu-xBi alloys increased with increasing Bi content. However, when the Bi content was >12 wt%, owing to the aggregation of Bi in the alloy, the corrosion resistance of the alloy decreased.

Electrocatalytic CO 2 Reduction over Bimetallic Bi-Based Catalysts: A Review

Electrocatalytic CO ₂ Reduction over Bimetallic Bi-Based Catalysts: A Review