Addition Of Gallium Research Articles

Effects of annealing processes on properties and microstructure of sintered Nd-Fe-B magnet with gallium and copper additions

In this work, the properties and microstructure of sintered Nd-Pr-Fe-Co-Zr-Ga-Cu-B magnet prepared by the single-step annealing, double-step annealing, and triple-step annealing processes were studied. The triple-step annealed magnet exhibits the highest intrinsic coercivity of 19.72 kOe, which is a 58.5% enhancement relative to the as-sintered magnet, and has the best temperature stability of coercivity. The best continuity of grain boundary (GB) phase and the highest content of RE6Fe13Ga phase can be observed in the triple-step annealed magnet, along with relatively small grain size. After triple-step annealing process, the phase separation occurs at the triple-junction (TJ) region of the magnet, which is the Fe-rich phase identified as RE6Fe13Ga and the Fe-poor phase identified as Ia-RE2O3. The Ia-RE2O3 phase located at the corner of the TJ region can extend between the grains of (Nd,Pr)2Fe14B main phase to form the GB phase with a Fe content of less than 15 at%, thereby enhancing the magnetic isolation effect. The lattice misfit between the Ia-RE2O3 phase and the adjacent main phase is less than 5%, which is helpful to reduce defects at the edges of the main phase grains, thus reducing the nucleation of reverse domains.

Development of Novel Antibacterial Ti-Nb-Ga Alloys with Low Stiffness for Medical Implant Applications.

With the rising demand for medical implants and the dominance of implant-associated failures including infections, extensive research has been prompted into the development of novel biomaterials that can offer desirable characteristics. This study develops and evaluates new titanium-based alloys containing gallium additions with the aim of offering beneficial antibacterial properties while having a reduced stiffness level to minimise the effect of stress shielding when in contact with bone. The focus is on the microstructure, mechanical properties, antimicrobial activity, and cytocompatibility to inform the suitability of the designed alloys as biometals. Novel Ti-33Nb-xGa alloys (x = 3, 5 wt%) were produced via casting followed by homogenisation treatment, where all results were compared to the currently employed alloy Ti-6Al-4V. Optical microscopy, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) results depicted a single beta (β) phase microstructure in both Ga-containing alloys, where Ti-33Nb-5Ga was also dominated by dendritic alpha (α) phase grains in a β-phase matrix. EDS analysis indicated that the α-phase dendrites in Ti-33Nb-5Ga were enriched with titanium, while the β-phase was richer in niobium and gallium elements. Mechanical properties were measured using nanoindentation and microhardness methods, where the Young's modulus for Ti-33Nb-3Ga and Ti-33Nb-5Ga was found to be 75.4 ± 2.4 and 67.2 ± 1.6 GPa, respectively, a significant reduction of 37% and 44% with respect to Ti-6Al-4V. This reduction helps address the disproportionate Young's modulus between titanium implant components and cortical bone. Importantly, both alloys successfully achieved superior antimicrobial properties against Gram-negative P. aeruginosa and Gram-positive S. aureus bacteria. Antibacterial efficacy was noted at up to 90 ± 5% for the 3 wt% alloy and 95 ± 3% for the 5 wt% alloy. These findings signify a substantial enhancement of the antimicrobial performance when compared to Ti-6Al-4V which exhibited very small rates (up to 6.3 ± 1.5%). No cytotoxicity was observed in hGF cell lines over 24 h. Cell morphology and cytoskeleton distribution appeared to depict typical morphology with a prominent nucleus, elongated fibroblastic spindle-shaped morphology, and F-actin filamentous stress fibres in a well-defined structure of parallel bundles along the cellular axis. The developed alloys in this work have shown very promising results and are suggested to be further examined towards the use of orthopaedic implant components.

Gallium-containing mesoporous nanoparticles influence in-vitro osteogenic and osteoclastic activity

Mesoporous silica nanoparticles were synthesized using a microemulsion-assisted sol-gel method, and calcium, gallium or a combination of both, were used as dopants. The influence of these metallic ions on the physicochemical properties of the nanoparticles was investigated by scanning and transmission electron microscopy, as well as N2 adsorption-desorption methods. The presence of calcium had a significant impact on the morphology and textural features of the nanoparticles. The addition of calcium increased the average diameter of the nanoparticles from 80 nm to 150 nm, while decreasing their specific surface area from 972 m2/g to 344 m2/g. The nanoparticles of all compositions were spheroidal, with a disordered mesoporous structure. An ion release study in cell culture medium demonstrated that gallium was released from the nanoparticles in a sustained manner. In direct contact with concentrations of up to 100 μg/mL of the nanoparticles, gallium-containing nanoparticles did not exhibit cytotoxicity towards pre-osteoblast MC3T3-E1 cells. Moreover, in vitro cell culture tests revealed that the addition of gallium to the nanoparticles enhanced osteogenic activity. Simultaneously, the nanoparticles disrupted the osteoclast differentiation of RAW 264.7 macrophage cells. These findings suggest that gallium-containing nanoparticles possess favorable physicochemical properties and biological characteristics, making them promising candidates for applications in bone tissue regeneration, particularly for unphysiological or pathological conditions such as osteoporosis.

Gallium-Containing Materials and Their Potential within New-Generation Titanium Alloys for Biomedical Applications.

With the rising demand for implantable orthopaedic medical devices and the dominance of device-associated infections, extensive research into the development of novel materials has been prompted. Among these, new-generation titanium alloys with biocompatible elements and improved stiffness levels have received much attention. Furthermore, the development of titanium-based materials that can impart antibacterial function has demonstrated promising results, where gallium has exhibited superior antimicrobial action. This has been evidenced by the addition of gallium to various biomaterials including titanium alloys. Therefore, this paper aims to review the antibacterial activity of gallium when incorporated into biomedical materials, with a focus on titanium-based alloys. First, discussion into the development of new-generation Ti alloys that possess biocompatible elements and reduced Young's moduli is presented. This includes a brief review of the influence of alloying elements, processing techniques and the resulting biocompatibilities of the materials found in the literature. The antibacterial effect of gallium added to various materials, including bioglasses, liquid metals, and bioceramics, is then reviewed and discussed. Finally, a key focus is given to the incorporation of gallium into titanium systems for which the inherent mechanical, biocompatible, and antibacterial effects are reviewed and discussed in more detail, leading to suggestions and directions for further research in this area.

Effect of minor gallium addition on corrosion, passivity, and antibacterial behaviour of novel β-type Ti–Nb alloys

Metastable Ti–Nb alloys are promising bone-implant materials due to improved mechanical biofunctionality and biocompatibility. To overcome increasing bacterial infection risk, alloying with antibacterial elements is a promising strategy. This study investigates the effect of minor gallium (Ga) additions (4, 8 wt% Ga) to as-cast and solution-treated β-type Ti–45Nb-based alloy (96(Ti–45Nb)-4Ga, 92(Ti–45Nb)-8Ga (wt.%)) on corrosion and passive film properties, as well as cytocompatibility and antibacterial activity. The electrochemical properties were evaluated by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and Mott-Schottky analyses in phosphate-buffered saline (PBS). X-ray photoelectron spectroscopy (XPS) was performed to analyze the chemical composition of passive films. Early adhesion and viability of macrophages and Staphylococcus aureus were assessed by nucleocounting and colony-forming unit counting, respectively. The results showed that high corrosion resistance and passive film properties of Ti–45Nb are retained and even slightly improved with Ga. EIS results revealed that Ga addition improves the passive film resistance. XPS measurements of 92(Ti–45Nb)-8Ga show that the passive film contains Ti-, Nb- and Ga-based oxides, implying the formation of mixed (Ti–Nb-Ga) oxides. In addition, marginal Ga ion release rate was detected under free corrosion conditions. Therefore, it can be assumed that Ga species may contribute to passive film formation on Ga-containing alloys. The 92(Ti–45Nb)-8Ga elicited an antibacterial effect against S. aureus compared to cp-Ti at 4 h. Moreover, Ga-containing alloys showed good cytocompatibility with THP-1 macrophages at 24 h. In conclusion, it was demonstrated that Ga additions to Ti–45Nb are beneficial to corrosion resistance and showed promising initial host and bacterial interactions.

Effect of Ga3+ and In3+ Ions on the Anodic Dissolution of Aluminum in KOH Ethanol Solutions

The anodic dissolution of aluminum in the KOH ethanol solutions is considered. It is shown that an addition of gallium and indium compounds to the 2 M KOH solution in 96% ethanol leads to an abrupt increase in the anodic dissolution current of aluminum near the open-circuit potential and its shift by 300 mV toward negative values. The discharge galvanostatic curves in the solutions with the additives of gallium and indium compounds contain a flat discharge plateau at the current densities up to 4 mA/cm2. The hydrogen evolution rate in a number of KOH ethanol solutions is measured.

Novel low modulus beta-type Ti–Nb alloys by gallium and copper minor additions for antibacterial implant applications

This study aims to develop novel low-modulus, corrosion-resistant Ti-based alloys with enhanced antimicrobial properties for bone-related implant applications. Novel β-type (Ti–45Nb)-based alloys with minor additions of the antibacterial elements Ga and/or Cu (up to 4 wt.%) were produced by a two-step casting process followed by homogenization treatment. Three nominal compositions (Ti–45Nb)96-4 Ga, (Ti–45Nb)96–4Cu and (Ti–45Nb)96-2 Ga–2Cu (wt.%) were prepared based on alloy design approach using [Mo]eq and electron per atom (e/a) ratio. The influence of Ga and/or Cu addition on the phase constitution, mechanical response and corrosion characteristics in simulated body fluids (PBS, 37.5 °C) has been investigated. X-ray diffraction studies displayed a single β phase structure for all alloys, with an observed lattice contraction evidenced by the reduction of lattice parameters during Rietveld analysis. Homogenous equiaxed microstructures with grain sizes ranging from 55 μm up to 323 μm were observed for (Ti–45Nb)96-4 Ga, (Ti–45Nb)96-2 Ga–2Cu and (Ti–45Nb)96–4Cu alloys. The alloys displayed excellent plasticity with no cracking, or fracturing during compression tests. Their tensile strength, Young's modulus, maximum tensile strain and elastic energy were measured in the ranges of 544–681 MPa, 73–78 GPa, 17–28% and 2.5–3.7 MJ/m3, in the order (Ti–45Nb)96-4 Ga > (Ti–45Nb)96-2 Ga–2Cu > (Ti–45Nb)96–4Cu. In addition, it has been observed that micro-alloying Ti–Nb alloy with Ga and/or Cu posed no deleterious effect on the corrosion resistance in simulated body fluid conditions. The improvement in strength of the developed alloys has been discussed based on grain boundary and solid-solution strengthening, whereas the improved plasticity is attributed to work hardening.

How much gallium do we need for a p-type Cu(In,Ga)Se2?

Doping in the chalcopyrite Cu(In,Ga)Se2 is determined by intrinsic point defects. In the ternary CuInSe2, both N-type conductivity and P-type conductivity can be obtained depending on the growth conditions and stoichiometry: N-type is obtained when grown Cu-poor, Se-poor, and alkali-free. CuGaSe2, on the other hand, is found to be always a P-type semiconductor that seems to resist all kinds of N-type doping, no matter whether it comes from native defects or extrinsic impurities. In this work, we study the N-to-P transition in Cu-poor Cu(In,Ga)Se2 single crystals in dependence of the gallium content. Our results show that Cu(In,Ga)Se2 can still be grown as an N-type semiconductor until the gallium content reaches the critical concentration of 15%–19%, where the N-to-P transition occurs. Furthermore, trends in the Seebeck coefficient and activation energies extracted from temperature-dependent conductivity measurements demonstrate that the carrier concentration drops by around two orders of magnitude near the transition concentration. Our proposed model explains the N-to-P transition based on the differences in formation energies of donor and acceptor defects caused by the addition of gallium.

Highly Elastic, Sensitive, Stretchable, and Skin-Inspired Conductive Sodium Alginate/Polyacrylamide/Gallium Composite Hydrogel with Toughness as a Flexible Strain Sensor.

As a classic flexible material, hydrogels show great potential in wearable electronic devices. The application of strain sensors prepared using them in human health monitoring and humanoid robotics is developing rapidly. However, it is still a challenge to fabricate a high-toughness, large-tensile-deformation, strain-sensitive. and human-skin-fit hydrogel with the integration of excellent mechanical properties and high electrical conductivity. In this study, a flexible sensor using a highly strain-sensitive skin-like hydrogel with acrylamide and sodium alginate was designed using liquid metallic gallium as a "reactive" conductive filler. The sensor had a low elastic modulus (30 kPa) similar to that of skin, a high-toughness (2.25 MJ m-3), self-stiffness, a large tensile deformation (1400%), recoverability, and excellent fatigue resistance. Moreover, the addition of gallium might enhance the electrical conductivity (1.9 S m-1) of the hydrogel while maintaining high transparency, and the flexible sensor device constructed from it showed high sensitivity to strain (gauge factor = 4.08) and pressure (gauge factor = 0.455 kPa-1). As a result, the hydrogel sensor could monitor various human motions, including large-scale joint bending and tiny facial expression, breathing, voice recognition, and handwriting. Furthermore, it might even be used for human-computer communication.

From Al-SBA-15 to Ga-SBA-15: Morphology and acidity evolution in the acid-free synthesis

Tuning the morphological and acidic properties of mesoporous molecular sieve materials is highly valuable for catalyst design towards the reactions involving large molecules. In this work, a series of Ga-containing SBA-15 ordered mesoporous materials (OMMs) were synthesized following the acid-free strategy. Ga-SBA-15 exhibits an acid amount of 0.48 mmol/g, comparable to the Al-SBA-15 (0.45 mmol/g). In addition, it is found that the straight short stick particles of Al-SBA-15 integrally bended upon a replacement of Al with Ga and the tendency continuous with the incremental addition of gallium, until fully transforms into the highly dispersed isolated bending particles of Ga-SBA-15. Owing to the improved interparticle-type mesoporosity derived from the dispersed bending particles, the active sites on external surface are highly accessible for large molecules. As for the acidic property, the Brönsted-type acidic property of Al-SBA-15 changed to the Lewis-type acidity with the replacement of gallium. In the Ga-SBA-15 case, more than 93% of strong acid sites were confirmed as Lewis characteristic. On the other hand, Low Density Polyethylene (LDPE) exhibits a faster decomposition rate over Ga-SBA-15 than Al-SBA-15 and Al–Ga bimetallic doped SBA-15 (galloaluminosilicate) catalysts. • Ga-containing SBA-15 mesoporous materials were synthesized following the acid-free strategy. • Replacement of Al with Ga induces a morphological evolution from the straight short stick to a bending shape. • Ga-SBA-15 exhibits strong Lewis acidity and hierarchical pore structure solely composed of interparticle-type mesopores.

Borderline first-order magnetic phase transition in AlFe2B2

The thermal evolution of lattice parameters coupled with heat capacity data provide insight into tailorable magnetism-structure attributes in the orthorhombic compound AlFe2B2 that was synthesized with and without small additions of gallium. Temperature-dependent X-ray powder diffraction experiments conducted through the magnetic phase transition reveal that the a- and b-parameters of both samples increase with increasing temperature while the c-parameter decreases. While a weak volumetric thermal expansion is noted over a range of temperatures well below and above the magnetic phase transition, anomalous behavior was observed within the phase transition region itself to reveal a magnetostructural phase transition with borderline first-order character in the Ga-modified sample but of more second-order character in the Ga-free sample. It is established that the nearest-neighbor Fe-Fe interatomic distance within the (ab)-plane plays a dominant role in influencing the magneto-functional response of these compounds. The magnetocaloric properties are discussed in the context of temperature-induced changes of the interatomic bonding that are influenced by the hypothesized presence of iron antisite defects in the AlFe2B2 lattice.

An Improved Methodology for Determination of Fluorine in Biological Samples Using High-Resolution Molecular Absorption Spectrometry via Gallium Fluorine Formation in a Graphite Furnace

Nowadays growing attention is paid to the control of fluorine content in samples of biological origin as it is present in the form of various biologically active organic compounds. Due to the chemically-rich matrix of biological tissues, the determination of fluorine becomes a very difficult task. Furthermore, a required complex sample preparation procedure makes the determination of the low contents of F by ion chromatography UV-Vis or ion-selective electrodes not possible. High-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS GF MAS) seems to be the best option for this purpose due to its high robustness to matrix interferences, especially in the presence of carefully selected modifiers. In this work the possibility of quantitative F determination in water and animal tissues was examined by measuring the molecular absorption of gallium monofluoride (GaF) at 211.248 nm with the use of a commercially available HR-CS GF MAS system. Experimental conditions for the sensitive and precise determination of fluorine were optimized, including the time/temperature program as well as addition of gallium and modifier mixture in combined mode. Under these conditions the fluoride present in the sample was stabilized up to 600 °C, and the optimum vaporization temperature for GaF was 1540 °C. Palladium and zirconium deposited onto the graphite surface served as solid modifiers; sodium acetate and ruthenium modifiers were added directly to the sample. The limit of detection and the characteristic mass of the method were 0.43 μg/L and 8.7 pg, respectively. The proposed procedure was validated by the use of certified reference materials (CRMs) of lake water and animal tissue; the acceptable recovery was obtained, proving that it can be applied for samples with a similar matrix.

ВЛИЯНИЕ ДОБАВОК ГАЛЛИЯ НА ТЕПЛОЕМКОСТЬ И ТЕРМОДИНАМИЧЕСКИЕ ФУНКЦИИ АЛЮМИНИЕВОГО СПЛАВА АЖ5К10

Heat capacity is the most important characteristic of substances, and from its change with temperature one can determine the type of phase transformation, Debye temperature, energy of vacancy formation, coefficient of electronic heat capacity and other properties. In this work, the heat capacity of the АЖ5К10 aluminum alloy was determined in the "cooling" mode, according to the known heat capacity of a reference sample made of M00 copper. To do that, the equations describing their cooling rates were obtained by processing the cooling curves of the samples from the alloys of the АЖ5К10-Ga system and the standard. Further, according to the experimentally found values of the cooling rates of the samples from the alloys and the standard, knowing their masses, the polynomials of the temperature dependence of the heat capacity of the alloys were established, which are described by a four-term equation. Using integrals of specific heat capacity, the temperature dependence of changes in enthalpy, entropy and Gibbs energy was calculated. The obtained dependences show that with an increase in temperature, the heat capacity, heat transfer coefficient, enthalpy and entropy of alloys increase, while the values of the Gibbs energy decrease. In that case, the addition of gallium reduces the heat capacity, enthalpy, and entropy of the АЖ5К10 alloy, while the value of the Gibbs energy increases

From Dislocation to Nano‐Precipitation: Evolution to Low Thermal Conductivity and High Thermoelectric Performance in n‐Type PbTe

AbstractPbTe‐based alloys have been widely used as mid‐temperature thermoelectric (TE) materials since the 1960s. Years of endeavor spurred the tremendous advances in their TE performance. The breakthroughs for n‐type PbTe have been somewhat less impressive, which limits the overall conversion efficiency of a PbTe‐based TE device. In light of this obstacle, an n‐type Ga‐doped PbTe via an alternative thermodynamic route that relies on the equilibrium phase diagram and microstructural evolution is revisited. Herein, a plateau of zT = 1.2 is achieved in the best‐performing Ga0.02Pb0.98Te in the temperature range of 550–673 K. Notably, an extremely high average zTave = 1.01 is obtained within 300 − 673 K. The addition of gallium optimizes the carrier concentration and boosts the power factor PF = S2ρ−1. Meanwhile, the κL of Ga‐PbTe reveals a significantly decreasing tendency owing to the defect evolution that changes from dislocation loop to nano‐precipitation with increasing Ga content. The pathway for both the κL reduction and defect evolution can be probed by an equilibrium phase diagram, which opens up a new avenue for locating high zT TE materials.

Intensification of Hydrogen Generation through Liquid Metal Gallium in Water Splitting Reaction Using Aluminum in Presence of Potassium Hydroxide

The present study reports the effect of the addition of room temperature liquid metal gallium on hydrogen generation in water splitting reaction using aluminum. The various proportions of gallium used were 13%, 23%, 33% and 50% weight by weight gallium of the total weight of metals (aluminum and gallium) in the reaction. The hydrogen generation at these additions of gallium was studied at various concentrations of aqueous KOH viz. 1 N, 1.5 N and 2 N and at various reaction temperatures of 50, 60 and 70 oC. The optimum proportion of gallium was found to be 23% at which the hydrogen generation rate was found to be thrice than the hydrogen generation rate without. The temperature of the reaction was observed to be dominant over the gallium addition at 60 and 70 oC. The gallium used in the reaction was completely recovered and reused in the reaction.

Conversion of furan over gallium and zinc promoted ZSM-5: The effect of metal and acid sites

The addition of gallium or zinc to ZSM-5 increases the aromatic selectivity and decreases the olefin selectivity for furan conversion. Both the benzene and naphthalenes selectivities increase with small amounts of gallium or zinc addition. At 5 wt% metal loading this effect is more pronounced with zinc promoted ZSM-5 having about 25% higher benzene selectivity than the gallium promoted ZSM-5. Additionally, the decarbonylation and methane formation reactions were both increased by adding zinc or gallium to the catalyst. As zinc or gallium loading is increased, the amount of Brønsted acid sites decrease, while the quantity of Lewis acid sites increase. This effect was more pronounced with zinc, as a result of its greater effectiveness to exchange with protons at the Brønsted acid sites. The aromatic yield appears to correlate with this increase in Lewis acidity. The addition of zinc to ZSM-5 also altered the reaction chemistry occurring during the hydrolysis of furan, lowering propylene and increasing methane yields as zinc loading increased.

Enhanced Water Oxidation Activity by Introducing Gallium into Cobalt‐Iron Oxide System

AbstractDevelopment of high‐efficiency and robust multi‐element transition metal oxides for oxygen evolution reaction (OER) is crucial to improve the energy efficiency of electrocatalytic water splitting. Here, we report a simple and efficient sol‐gel strategy to synthesize an amorphous ternary Fe−Co−Ga oxide composite with high OER activity, low Tafel slope, and good durability. The overpotential at 10 mA ⋅ cm−2 of the FeCoGaOx on glassy carbon, platinum, carbon paper, and nickel foam electrode is 245, 275, 237, and 215 mV, respectively, in an alkaline electrolyte. The addition of gallium into the FeCoOx system significantly promotes the charge transfer kinetics, thus improving the OER activity. This work affords a controllable method to vastly prepare cost‐effective and high‐efficiency multi‐metal water oxidation electrocatalysts.

Intensification of hydrogen generation through liquid metal gallium in water splitting reaction using aluminum in presence of potassium hydroxide

The present study reports the effect of the addition of room temperature liquid metal gallium on hydrogen generation in water splitting reaction using aluminum. The various proportions of gallium used were 13%, 23%, 33% and 50% weight by weight gallium of the total weight of metals (aluminum and gallium) in the reaction. The hydrogen generation at these additions of gallium was studied at various concentrations of aqueous KOH viz. 1 N, 1.5 N and 2 N and at various reaction temperatures of 50, 60 and 70 °C. The optimum proportion of gallium was found to be 23% at which the hydrogen generation rate was observed thrice than the hydrogen generation rate in absence of gallium. The temperature of the reaction was observed to be dominant over the gallium addition at 60 and 70 °C. The gallium used in the reaction was completely recovered and reused in the reaction.

Hydrogen generation through water splitting reaction using waste aluminum in presence of gallium

The in-situ hydrogen generation through water splitting reaction using waste aluminum wires has been studied in presence of room temperature liquid metal gallium and alkaline activator potassium hydroxide. Various proportions of gallium i.e. 50%, 75%, 90% and 95% (weight by weight of the total metal in reaction) were used in order to study the effect of gallium addition on the water splitting reaction. The effect of addition of gallium on the water splitting reaction was also studied and co-related with various concentrations of activator (0.5 N and 1.0 N aqueous KOH) and reaction temperature (50, 60 and 70 °C). The effect of gallium was found to be more prominent at 0.5 N and 50 °C as compare to the 1.0 N and higher temperatures of 50 and 60 °C. The 12 fold increase in hydrogen generation rate was observed for 0.5 N aqueous KOH at 90% gallium addition and 1.0 N aqueous KOH at 75% gallium addition. The added gallium was completely recovered from the reaction. The Shrinking Core Model has been applied to the experimental data for predicting the rate controlling mechanism. The diffusion was predicted as the rate controlling step for maximum cases.

Effects of indium, gallium, or bismuth additions on the discharge behavior of Al-Mg-Sn-based alloy for Al-air battery anodes in NaOH electrolytes

In this paper, the electrochemical performances of Al 0.5-Mg 0.1-Sn (wt%), Al 0.5-Mg 0.1-Sn 0.05 In (wt%), Al 0.5-Mg 0.1-Sn 0.05 Ga (wt%) and Al 0.5-Mg 0.1-Sn 0.05 Bi (wt%) alloys were investigated through electrochemical techniques and microstructure observation in 4 M NaOH solution. The results indicate that Al 0.5-Mg 0.1-Sn 0.05 In (wt%) alloy has the best discharge performance among all alloys, followed by Al 0.5-Mg 0.1-Sn 0.05-Bi (wt%) alloy, both of which is better than Al 0.5 Mg 0.1-Sn 0.05-Ga (wt%) alloy. This is due to the fact that the addition of indium to the Al 0.5-Mg 0.1-Sn-based alloy improves the discharge activity of the alloy while increasing its anodic efficiency. Although the addition of gallium or bismuth to this alloy increases the discharge activity, it reduces the efficiency of the anode, especially the addition of gallium resulting in severe intergranular corrosion of the alloy anode.