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Zn-Ag-Cu alloys have recently attracted attention as alloy candidates for biomedical applications, but, to date, they have not achieved the required mechanical properties. To improve the mechanical properties of Zn-Ag-Cu-base alloys, in this work, the effects of the presence of increasing amounts of Ag and Cu as alloying elements on the properties of four 0.05% Mg-micro-alloyed Zn-Ag-Cu base alloys are explored. The alloys were manufactured in an electric furnace with a protective atmosphere using increasing amounts of Ag and Cu as alloying agents, and were cast in a metallic mold. The samples obtained were thermomechanically processed by hot extrusion. Three of the four alloys under study presented increasing amounts of the second phase (Ag, Cu)Zn4, high mechanical properties, a microstructure and mechanical behavior characteristic of heteromaterials with a heterogeneous lamella-structure, and met the requirements of the mechanical properties, corrosion rate, antibacterial properties against S. aureus, and the cytotoxicity required for biomedical applications. It seems possible to tune the properties of the ZnAgCu-0.05% Mg alloys by changing the Ag and Cu contents. [ABSTRACT FROM AUTHOR]

Zn-Ag-Cu alloys have recently attracted attention as alloy candidates for biomedical applications, but, to date, they have not achieved the required mechanical properties. To improve the mechanical properties of Zn-Ag-Cu-base alloys, in this work, the effects of the presence of increasing amounts of Ag and Cu as alloying elements on the properties of four 0.05% Mg-micro-alloyed Zn-Ag-Cu base alloys are explored. The alloys were manufactured in an electric furnace with a protective atmosphere using increasing amounts of Ag and Cu as alloying agents, and were cast in a metallic mold. The samples obtained were thermomechanically processed by hot extrusion. Three of the four alloys under study presented increasing amounts of the second phase (Ag, Cu)Zn4, high mechanical properties, a microstructure and mechanical behavior characteristic of heteromaterials with a heterogeneous lamella-structure, and met the requirements of the mechanical properties, corrosion rate, antibacterial properties against S. aureus, and the cytotoxicity required for biomedical applications. It seems possible to tune the properties of the ZnAgCu-0.05% Mg alloys by changing the Ag and Cu contents.

This study focuses on the preparation and characterization of zinc-based alloys containing magnesium, calcium, and manganese. The alloys were prepared by the melting of pure elements, casting them into graphite molds, and thermo-mechanically treating them via hot extrusion. The phase compositions of the samples were analyzed using X-ray diffraction technique and SEM/EDX analysis. The analysis confirmed that in addition to the Zn matrix, the materials are reinforced by the CaZn13, MgZn2, and Mn-based precipitates. The mechanical properties of the alloys were ascertained by tensile, compressive, and bending tests, measurement of the samples microhardness and elastic modulus. The results indicate that an increase in Mn content leads to an increase in the maximum stress experienced under both tension and compression. However, the plastic deformation of the alloys decreases with increasing Mn content. This study provides valuable insights into the microstructural changes and mechanical behavior of zinc-based alloys containing magnesium, calcium, and manganese, which can be used to design alloys for specific biomedical applications. [ABSTRACT FROM AUTHOR]

An incomplete understanding of the cellular functions and underlying mechanisms of zinc ions released from zinc‐based stents in atherosclerosis (AS) therapy is one of the major obstacles to their clinical translation. The existing evaluation methodology using cell monolayers has limitations on accurate results due to the lack of vascular architectures and pathological features. Herein, the authors propose a 3D biomimetic AS model based on a multi‐layer vascular structure comprising endothelial cells and smooth muscle cells with hyperlipidemic surroundings and inflammatory stimulations as AS‐prone biochemical conditions to explore the biological functions of zinc ions in AS therapy. Concentration‐dependent biphasic effects of zinc ions on cell growth are observed both in cell monolayers and 3D AS models. Nevertheless, the cells within 3D AS model exhibit more accurate biological assessments of the zinc ions, as evidenced by augmented pathological features and significantly higher half‐maximal inhibitory concentration values against zinc ions. Based on such a developed 3D biomimetic AS model, the inhibitory effects on the deoxyribonucleic acid (DNA) synthesis, significantly influenced biological processes like cell motility, proliferation, and adhesion, and several potential bio‐targets of zinc ions of cells are revealed. [ABSTRACT FROM AUTHOR]

Abstract An incomplete understanding of the cellular functions and underlying mechanisms of zinc ions released from zinc‐based stents in atherosclerosis (AS) therapy is one of the major obstacles to their clinical translation. The existing evaluation methodology using cell monolayers has limitations on accurate results due to the lack of vascular architectures and pathological features. Herein, the authors propose a 3D biomimetic AS model based on a multi‐layer vascular structure comprising endothelial cells and smooth muscle cells with hyperlipidemic surroundings and inflammatory stimulations as AS‐prone biochemical conditions to explore the biological functions of zinc ions in AS therapy. Concentration‐dependent biphasic effects of zinc ions on cell growth are observed both in cell monolayers and 3D AS models. Nevertheless, the cells within 3D AS model exhibit more accurate biological assessments of the zinc ions, as evidenced by augmented pathological features and significantly higher half‐maximal inhibitory concentration values against zinc ions. Based on such a developed 3D biomimetic AS model, the inhibitory effects on the deoxyribonucleic acid (DNA) synthesis, significantly influenced biological processes like cell motility, proliferation, and adhesion, and several potential bio‐targets of zinc ions of cells are revealed.

Zn-based materials have attracted increasing attention in the biodegradable materials field due to their unique combination of suitable biodegradability and good biological functionalities. However, the currently existing Zn alloys exhibited poor mechanical reliability and insufficient anti-bacterial activity. In this study, the microstructure, mechanical properties, corrosion behavior and antibacterial properties of Zn-1Cu-0.5Ag and Zn-1Cu-1Ag alloys were investigated. The average grain size of the alloys decreased from 1.91 μm in the Zn-1Cu-0.5Ag alloy to 1.64 μm in the Zn-1Cu-1Ag alloy with the increasing Ag concentration. Due to the grain refinement effect, Zn-1Cu-1Ag exhibited higher ductility (elongation of 36.0%) compared with its Zn-1Cu-0.5Ag counterparts (elongation of 26.3%). In the meantime, the Zn-1Cu-1Ag alloy possessed the ultimate tensile strength (UTS) of 292.04 MPa, the yield strength (YS) of 269.49 MPa, and the Vickers hardness value of 96.9. The anti-bacterial properties of the material were evaluated by the inhibition zone test. The addition of Cu and Ag endowed strong anti-bacterial activity to staphylococcus aureus (S. aureus) and escherichia coli (E. coli) with the zinc matrix. The Zn-1Cu-1Ag alloy exhibited improved mechanical properties, a moderate degradation rate of 0.0484 mm/y, acceptable cytocompatibility, and efficient anti-bacterial properties which should be useful for orthopedic applications. [ABSTRACT FROM AUTHOR]

The surface of the copper metal was successfully coated with a certain thickness of zinc-nickel-molybdenum (ZnNiMo) alloy by applying the chronopotentiometry technique. Then PANi and PPy homopolymer films were synthesized on the ZnNiMo coated Cu surface (Cu/ZnNiMo) in an aqueous sodium oxalate solution containing molybdate ion at certain concentrations. PANi and PPy film synthesis conditions were modelled by RSM applying Box-Behnken design by using three factors as molybdate ion concentration, monomer concentration and scan rate. Thus, the optimal synthesis conditions of PANi and PPy films on the Cu/ZnNiMo electrode were determined by evaluating anticorrosion performances. It has been determined that the relationship between the corrosion resistance of PANI and PPy films and the studied parameters can be modeled with quadratic and 2FI equations, respectively. The surface diagrams obtained for PPy were very interesting in that they showed that the change in any of the operating parameters reversed the change of the response depending on the other parameters. The anticorrosion properties of PANi and PPy homopolymer films that synthesized at their optimal conditions on Cu/ZnNiMo electrode surface were investigated by the Eocp-time curves, anodic polarization plots and AC impedance spectroscopy measurement, in 3.5% NaCl solution. PPy and PANi homopolymer films provided significant physical barrier property to Cu/ZnNiMo electrode. Besides, PANi film on Cu/ZnNiMo electrode surface exhibited significantly high more protection behavior in 3.5% NaCl solution than that of PPy. [ABSTRACT FROM AUTHOR]

This study focuses on the preparation and characterization of zinc-based alloys containing magnesium, calcium, and manganese. The alloys were prepared by the melting of pure elements, casting them into graphite molds, and thermo-mechanically treating them via hot extrusion. The phase compositions of the samples were analyzed using X-ray diffraction technique and SEM/EDX analysis. The analysis confirmed that in addition to the Zn matrix, the materials are reinforced by the CaZn13, MgZn2, and Mn-based precipitates. The mechanical properties of the alloys were ascertained by tensile, compressive, and bending tests, measurement of the samples microhardness and elastic modulus. The results indicate that an increase in Mn content leads to an increase in the maximum stress experienced under both tension and compression. However, the plastic deformation of the alloys decreases with increasing Mn content. This study provides valuable insights into the microstructural changes and mechanical behavior of zinc-based alloys containing magnesium, calcium, and manganese, which can be used to design alloys for specific biomedical applications.

Implant-associated infection (IAI) is one of the major challenges in orthopedic surgery. The development of implants with inherent antibacterial properties is an effective strategy to resolve this issue. In recent years, biodegradable alloy materials have received considerable attention because of their superior comprehensive performance in the field of orthopedic implants. Studies on biodegradable alloy orthopedic implants with antibacterial properties have gradually increased. This review summarizes the recent advances in biodegradable magnesium- (Mg-), iron- (Fe-), and zinc- (Zn-) based alloys with antibacterial properties as orthopedic implant materials. The antibacterial mechanisms of these alloy materials are also outlined, thus providing more basis and insights on the design and application of biodegradable alloys with antibacterial properties as orthopedic implants.

Zn-based materials have attracted increasing attention in the biodegradable materials field due to their unique combination of suitable biodegradability and good biological functionalities. However, the currently existing Zn alloys exhibited poor mechanical reliability and insufficient anti-bacterial activity. In this study, the microstructure, mechanical properties, corrosion behavior and antibacterial properties of Zn-1Cu-0.5Ag and Zn-1Cu-1Ag alloys were investigated. The average grain size of the alloys decreased from 1.91 μm in the Zn-1Cu-0.5Ag alloy to 1.64 μm in the Zn-1Cu-1Ag alloy with the increasing Ag concentration. Due to the grain refinement effect, Zn-1Cu-1Ag exhibited higher ductility (elongation of 36.0%) compared with its Zn-1Cu-0.5Ag counterparts (elongation of 26.3%). In the meantime, the Zn-1Cu-1Ag alloy possessed the ultimate tensile strength (UTS) of 292.04 MPa, the yield strength (YS) of 269.49 MPa, and the Vickers hardness value of 96.9. The anti-bacterial properties of the material were evaluated by the inhibition zone test. The addition of Cu and Ag endowed strong anti-bacterial activity to staphylococcus aureus (S. aureus) and escherichia coli (E. coli) with the zinc matrix. The Zn-1Cu-1Ag alloy exhibited improved mechanical properties, a moderate degradation rate of 0.0484 mm/y, acceptable cytocompatibility, and efficient anti-bacterial properties which should be useful for orthopedic applications.

Abstract The requirement of modification on primary Si particles at low temperature has restricted the development of inoculants in low pressure casting industries. In this paper, by dissolving Cu-14P master alloy into Zn melt and utilizing the diffusion of Zn atoms into Cu 3 P phase, a novel Zn-8.6Cu-1.4P master alloy has been synthesized. Except for η-Zn matrix, ε-CuZn 5 and α-Zn 3 P 2 are the main intermetallics. After introducing into A390 melt at a relatively low temperature (≤720 °C), the α-Zn 3 P 2 phase evolves to AlP, and the in-situ formed AlP nucleus exhibits attractive modification performance on primary Si. The Zn-Cu-P master alloy may be a promising candidate for application in low pressure casting industries. [ABSTRACT FROM AUTHOR]

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Implant-associated infection (IAI) is one of the major challenges in orthopedic surgery. The development of implants with inherent antibacterial properties is an effective strategy to resolve this issue. In recent years, biodegradable alloy materials have received considerable attention because of their superior comprehensive performance in the field of orthopedic implants. Studies on biodegradable alloy orthopedic implants with antibacterial properties have gradually increased. This review summarizes the recent advances in biodegradable magnesium- (Mg-), iron- (Fe-), and zinc- (Zn-) based alloys with antibacterial properties as orthopedic implant materials. The antibacterial mechanisms of these alloy materials are also outlined, thus providing more basis and insights on the design and application of biodegradable alloys with antibacterial properties as orthopedic implants., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Ma, Shi, Song, Guo and Yang.)

Abstract: In this study, the influence of microstructural alterations brought about by adding silicon on the slurry wear behaviour of a zinc-based alloy has been investigated. Wear tests were conducted using sample rotation method at a speed of 4.71m/s over a range of traversal distance and sand concentration in the test environment. The electrolyte (i.e. liquid part of the slurry) contained chloride and sulphate ions which are essential constituents of mine water. The study suggests maximum wear loss and rate of the samples in the liquid-only medium. The presence of suspended sand particles in the liquid led to substantially decrease the wear rate/loss. A comparison of the wear response of the samples in the liquid plus sand environments showed that intermediate concentration, i.e. 40%, of the suspended sand particles in the test environment caused maximum wear rate/loss. However, this was substantially less than the liquid-only medium. The wear loss increased with traversal distance. The slope of the wear loss versus traversal distance plots was high initially followed by a reduced slope at longer traversal distances. This trend was very clearly visible in the liquid-only environment. Increasing traversal distance initially led to higher wear rate. This was followed by the attainment of a wear rate peak, a reduction in wear rate and finally a steady state wear rate at longer traversal distances. The average (cumulative) wear rate versus average (cumulative) wear loss plots showed acceleration, steady state and deceleration zones depending on the test conditions. Silicon particles, generated as a result of silicon addition in the alloy system, led to improved wear behaviour. Observed wear characteristics of the samples have been explained on the basis of operating wear mechanisms such as corrosion, erosion and abrasion. Predominance of one mechanism of material removal over the other(s) and the nature of various reaction products formed on the affected surfaces were thought to be responsible for specific wear behaviour of the samples under a given set of conditions. Examination of affected surfaces and subsurface regions further supported the wear characteristics of the specimens. [Copyright &y& Elsevier]

The friction and wear of two near-eutectoid and two monotectoid permanent-moulded zinc-based alloys and an SAE 660 bronze for comparison were investigated under dry sliding conditions. To determine the wear mechanisms surface and subsurface microstructures of worn test samples were examined by scanning electron microscopy (SEM).All of the zinc-based alloys had lower coefficients of friction and higher wear resistance than the bronze; the best wear resistance and lowest coefficient of friction were obtained for the ZnAl40Cu2Si1 alloy. Wear resistance increased strongly with hardness and tensile strength and decreased with friction coefficient. Correlation of the experimental results showed that the wear behaviour of the zinc-based alloys was consistent with Archhard’s equation.Layered structures were formed under the wear surfaces of the zinc-based alloy samples during testing. The topmost layer, formed by smearing and embedding of oxidised zinc–aluminium alloy was hard and is considered to have contributed to their low wear rates. Surface and subsurface examinations showed that adhesion and smearing was the main wear mechanism for the zinc-based alloys, while abrasive wear dominated in the case of the SAE 660 bronze. [Copyright &y& Elsevier]

The lubricated wear behaviour of cast journal bearings, produced from a series of zinc-based alloys and SAE 660 bronze as a reference material, was investigated under both static and dynamic loading conditions using a bearing test rig. All of the zinc-based alloys had higher wear resistance than the SAE 660 bronze. Among the zinc-based alloys, the wear resistance of the monotectoid-based alloys was superior to those based on near-eutectoid composition, and the best wear performance under both static and dynamic loading conditions was obtained with ZnAl40Cu2Si1 alloy. Copper content affected the wear resistance of monotectoid zinc-based alloys. Under dynamic loading conditions, it increased with increasing copper content up to 2%, but declined thereafter. Tensile properties and hardness of the monotectoid alloys were also affected by their copper content. Loading conditions had a strong influence on the wear rate. Under static loading conditions, as-cast zinc-based alloys showed higher wear resistance than the equivalent heat-treated alloys, but this behaviour was reversed for dynamic loading. Possible reasons for this are briefly discussed. [Copyright &y& Elsevier]

This study analyzes the effects of test temperature and strain rate on the tensile properties of some copper-and zinc-based alloys. The copper-based alloys comprised a leaded-tin and an aluminum bronze, whereas the zinc-based alloys were added with various quantities of aluminum. The aluminum bronze attained maximum room-temperature tensile strength, whereas that of the leaded-tin bronze was the least. Among the zinc-based alloys, the one comprising 27.5 mass% aluminum exhibited superior tensile strength, followed by those alloyed with 11.5, 37.5, and 47.5 mass% aluminum in a descending order. Increasing strain rate tended to improve the tensile strength of the alloys. Tensile strength was reduced with an increase in test temperature irrespective of the alloy composition. The aluminum bronze possessed maximum strength regardless of temperature. The leaded-tin bronze attained least strength property at low temperatures, whereas higher test temperatures led to superior strength than the zinc-based alloys. The temperature sensitivity of the strength of the zinc-based alloys decreased with their aluminum content. Tensile elongation of the alloys tended to increase with an increase in strain rate and test temperature. Leaded-tin bronze was least affected in either case. The alloy also attained least elongation irrespective of test conditions. The aluminum bronze showed maximum elongation, at least at high strain rates. In the case of the zinc-based alloys, intermediate range of aluminum concentration led to better elongation. The elongation property of the alloys was affected by temperature in different manners. In a few cases, the elongation initially increased followed by a reduction beyond a specific test temperature, whereas, in other cases, a continuous increase with temperature was noted. The observations made have been discussed in terms of the nature of different microconstituents of the alloys whose effectiveness changes with test conditions. The response of the samples has been further substantiated with their fractographic features and subsurface characteristics. [ABSTRACT FROM AUTHOR]