Solid Solution Of Copper Research Articles

Synthesis of copper-doped nanocrystalline tin stannate by thermal decomposition of a precursor

Zinc hydroxostannate ZnSn(OH)6, containing 5 mol.% Cu, was obtained from hydrochloric acid solutions of tin(IV), zinc and copper by adding sodium hydroxide to pH = 8–9. The thermolysis process of the obtained sample and the phase composition of the decomposition products were studied using thermal analysis, X-ray diffraction, and scanning electron microscopy. It was shown that the main stages of dehydration are completed at a temperature of about 350 °C and, as a result of thermolysis, an X-ray amorphous product is formed, from which a solid solution of copper in zinc stannate is obtained at an annealing temperature above 650 °C. At an annealing temperature of 800 °C, a mixture of nanocrystalline tin dioxide SnO2 with a cassiterite structure and copper-doped zinc orthostannate Zn2SnO4 with a spinel structure is formed. The room temperature sensors based on ZnSnO3 and carbon nanofibers as a conductive additive showed high response to NO2 (–6.1% to 2 ppm NO2).

Synthesis and Tuning of Electronic, Optical, and Photoelectrochemical Properties of Copper Metavanadate Alloys via Alkaline Earth Metal Substitution

Unlike the well-studied and technologically advanced Group III-V and Group II-VI compound semiconductor alloys, alloys of ternary metal oxide semiconductors have only recently begun to receive widespread attention. Here, we describe the effect of alkaline earth metal substitution on the optical, electronic, and photoelectrochemical (PEC) properties of copper metavanadate (CuV2O6). As a host, the Cu-V-O compound family presents a versatile framework to develop such composition-property correlations. Alloy compositions of A0.1Cu0.9V2O6 (A = Mg, Ca) photoanodes were synthesized via a time and energy-efficient solution combustion synthesis (SCS) method. The effect of introducing alkaline earth metals (Mg, Ca) on the crystal structure, microstructure, electronic, and optical properties of copper metavanadates was investigated by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM), and Raman spectroscopy. The PXRD, TEM, and Raman spectroscopy data demonstrated the polycrystalline powder samples to be mutually soluble, solid solutions of copper and alkaline earth metal metavanadates and not simple mixtures of these compounds. The DRS data showed a systematic decrease in the optical bandgap with Cu incorporation. These trends were corroborated by electronic band structure calculations. Finally, the PEC properties exhibited a strong dependence on the alloy composition, pointing to possible applicability in solar water splitting, heterogeneous photocatalysis, phosphor lighting/displays, and photovoltaic devices.

Вивчення взаємодії інфрачервонопрозорих матеріалів ZnSe, ZnS, Si, Ge з розплавами металів

Wetting of infrared-transparent materials — selenide and sulfide zinc, germanium, and silicon by metal melts in a vacuum in a wide temperature range was studied by the sessile drop method using the method of capillary purification of the drop melt during the experiment. Pure metals In, Sn, Pb, Al, Fe, Ni, binary Al—Si, Ge—Si, In—Cu and multicomponent In—Sn—Cu—Ti alloys were used. When zinc chalcogenides are wetted with In—Sn—Cu—Ti melts, zinc selenide is wetted better than zinc sulfide. This is due to the lower thermodynamic stability of selenide. In systems where copper is present in melts, wetting is affected not only by the interaction of selenium or sulfur with titanium, but also by the interaction of copper and zinc (in the copper-zinc system, solid solutions of copper and zinc are formed and copper dissolves in solid zinc). This conclusion also confirms the wetting of the substrate by the In—Cu melt. The values of the contact angle at 650 C are equal to 32, which is less than for the In—Sn—Ti melt at the same temperature. It can be said that for such a system, the interaction of zinc with copper is very important, which is not inferior to the wetting effect of the interaction of chalcogens with titanium. The wetting of single crystals of germanium and silicon by metal melts improves with increasing temperature. Iron and nickel wet silicon (contact angles close to zero) at temperatures lower than their melting point. Contact melting also occurs when silicon substrates are wetted with aluminum melts (the eutectic in the Al—Si system has a temperature of 577 °C). Germanium is better wetted by tin than by indium and lead. Technological processes of soldering infrared transparent materials with metals were developed and soldered joints were obtained. Keywords: infrared transparent materials, polycrystalline zinc selenide and sulfide, single crystals of germanium and silicon, wetting, soldering.

Effect of copper interlayer to the microstructure and strength of alumina/304 stainless steel joint brazed with silver‐copper‐titanium filler

AbstractAlumina and 304 stainless steel were brazed with silver‐copper‐titanium filler+copper foil. The effect of adding copper foil to the filler on the microstructure of the alumina/304 joint was studied, and the reasons for the effect of adding copper foil with different thicknesses on the joint performance were also analyzed. The standard microstructure of alumina/304 joint with silver‐copper‐titanium+copper foil filler is alumina ceramic/copper compound with titanium and oxygen (3 : 3 : 1) (Cu3Ti3O) continuous layer+copper titanide (TiCu)/silver solid solution+copper solid solution/titanium compound with iron (1 : 2) (TiFe2)+iron‐chromium compound/304 stainless steel. The added copper foil inhibits the diffusion of titanium elements, thereby reducing the formation of the brittle copper compound with titanium and oxygen (3 : 3 : 1) (Cu3Ti3O) and alleviating the residual stress. In addition, after adding copper foil, the copper solid solution is distributed in blocks in the joint, which also improves the plastic deformation ability of the joint. Under the synergistic effect of these two effects after adding copper foil, the joint strength is improved. When the copper foil was 200 μm, the shear strength is 198.10 MPa.

An Effective Framework for Predicting Performance of Solid-Solution Copper Alloys Using a Feature Engineering Technique in Machine Learning

Utilized extensively in a myriad of industries, solid-solution copper alloys are prized for their superior electrical conductivity and mechanical properties. However, optimizing these often mutually exclusive properties poses a challenge, especially considering the complex interplay of alloy composition and processing techniques. To address this, we introduce a novel computational framework that employs advanced feature engineering within machine learning algorithms to accurately predict the alloy’s microhardness and electrical conductivity. Our methodology demonstrates a substantial enhancement over traditional data-driven models, achieving remarkable increases in R2 scores—from 0.939 to 0.971 for microhardness predictions and from −1.05 to 0.934 for electrical conductivity. Through machine learning, we also spotlight key determinants that significantly influence overall performance of solid-solution copper alloys, providing actionable insights for future alloy design and material optimization.

Comprehensive elemental screening of solid-solution copper alloys

Comprehensive elemental screening of solid-solution copper alloys

Enhancing Antibacterial Performance: Structure, Phase Composition, and Microroughness of Selective Plated Copper Coatings on Medical-Grade Stainless Steel 1.4021 and Nickel Alloy Ni200

This study presents a preliminary characterization of selective plated antibacterial copper coatings on medical-grade stainless steel 1.4021 and nickel alloy Ni200 substrates using two different copper electrolyte solutions with acidic and alkaline pH. The characterizations included analysis of the microstructure, phase composition, surface roughness, and antibacterial activity against Gram-positive Staphylococcus aureus ATCC 29213 and Gram-negative Escherichia coli ATCC 25922 bacteria. The results revealed uniform and continuous layers of single-phase solid-solution copper coatings without any cracks or defects. The coatings, produced using acidic or alkaline solutions, exhibited approximately 20% or 40% lower surface roughness compared to the substrate roughness. This suggests that the plating process led to a smoother surface finish. Importantly, all of the selective plated copper coatings exhibited antibacterial properties. Inhibition zones were identified, indicating the ability of the coatings to inhibit the growth of both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria. The use of the alkaline copper solution resulted in slightly larger inhibition zones compared to the acidic solution, indicating enhanced antibacterial activity. These findings suggest that the selective plated copper coatings on medical-grade stainless steel 1.4021 and nickel alloy Ni200 substrates have the potential to be effective antibacterial surfaces.

Dramatic improvement of the strength of laser welded joints of Nb521 to GH3128 by adding pure copper as an interlayer

Weld cracks and low weld strength of Nb521 to GH3128 dissimilar metal welded joint are key factors influencing their weldability. To obtain favorable crack-free laser welded joints, this research adopted copper as an interlayer to research the microstructure and properties of laser direct welded and laser offset welded joints of Nb521 to GH3128 superalloy. Compared to previous research results, the tensile strength of laser direct welded joints is enhanced by 2.5 folds. There is a melting reaction layer at the position where the center welded joints are adjacent to the Nb521 base metal, and Ni3Nb and Laves phases are present in the layer. The copper solid solution is located in the center of fusion zone, and Ni3Nb-Laves hard particles are found. The phases near the side of GH3128 superalloy base metal are Ni solid solution, Cu solid solution, Ni3Nb/Cr2Nb hard particles and high melting point alloy mixture. Macrosegregation at the laser offset welding fusion zone is more serious. The phases near the Nb521 base metal are Nb solid solution, Cu solid solution, Ni3Nb and Cu/Cr eutectic structure. At the center of the fusion zone, Cu solid solution, Ni3Nb and Cu/Cr eutectic structure are observed. The phases near GH3128 base metal are Ni solid solution, Cr2Nb phase and Cu solid solution. Mean Vickers hardness values of the direct welded fusion zone is 271.7 ± 129.8 HV, which reduces mismatching of hardness of the joints to a certain degree. As there are Laves phase and Ni3Nb brittle phase in the melting reaction layer adjacent to Nb521 base metal, the microhardness value is up to 589.1 HV. The average microhardness of the offset welded fusion zone is 449.1 ± 217.4 HV, which is higher than the hardness of Nb521 and GH3128 base metals, due to increasing number of brittle phases in the joints. Strength values of the direct welded and offset welded joints are 418.7 ± 49.8 MPa and 364.3 ± 24.5 MPa respectively, which are separately 86.0% and 74.8% of Nb521 base metal. Fractures are all found to occur at the fusion zone on the side of Nb521. The direct welded joints exhibit mixed fracture characteristics with dimples and cleavage facets on the fracture, while the offset welded joints are characterized by brittle fracture.

Microstructural evolution during low-temperature brazing of WC-Co cemented carbide to AISI 4140 steel using a silver-based filler alloy

The joining of cemented carbides to steels used in the drilling/excavation industries due to their distinct characteristics has posed a significant challenge. This research systematically investigates the effect of brazing temperature (650, 700, and 750 °C) and time (5, 10, and 15 min) as the most effective brazing parameters on the phase transformations and interfacial microstructure of WC-Co/AISI 4140 steel joints. Low-temperature brazing due to eliminating the destructive η carbides at the cermet interface, makes it a more appropriate procedure, as compared to fusion-welding methods, as per the findings of the current study. It was revealed that the optimal condition for the process is at 650 °C for a duration of 10 min, in which the eutectic structure is refined and the distribution of primary dendrites is uniform. The microstructure of the brazed area presents a multiphase structure, comprised of a copper-rich solid solution (Cu,Zn), a silver-rich solid solution (Ag,Cd), a eutectic structure as well as the β′-CuZn ordered phase. The β embedded in ternary eutectic structure was partially transformed to β′ during the cooling cycle of the brazing process. Diffusion of silver and cadmium in cemented carbide, as well as the formation of Co-Fe-Cu reaction product, were proposed as the bonding mechanisms. The effectiveness of brazing temperature in enlarging the cobalt-depleted zone appearing in WC-Co is comparatively higher than that of brazing time. It is also concluded that by increasing the brazing temperature and duration, the fraction of copper solid-solution dendrites distributed in the joint area decreases, however, the size increases.

Microstructural Evolution and Mechanical Properties of Cu/Ti Joints Welded by Ultrasonic Spot-Welding with Zn Interlayer

Cu/Ti dissimilar metals were joined together utilizing ultrasonic spot welding with a Zn interlayer. The threedimensional finite element analysis model was established to simulate the temperature field of the interface of Cu/Ti ultrasonic welding joint under different welding energies. The interface forming, microstructure, and mechanical properties of the Cu/Zn/Ti ultrasonic spot-welded joints were studied systematically. Results showed that the temperature distribution of the interface of the Cu/Zn/Ti ultrasonic welding joint was inhomogeneous, and the temperature of the interface below the indentation reached the highest and decreased gradually to the surrounding. With the increase of welding energy, the maximum temperature and the corresponding high-temperature region of Cu/Zn/Ti joint interface gradually increased. The interface of Cu/Zn/Ti ultrasonic welding joint was well formed, and the thickness was different, and the local position had wavy undulation morphology. When the welding energy was low, the interface microstructure was mainly composed of copper solid solution and titanium solid solution. As the welding energy increased, the microstructure of the joint interface was composed of CuZn compound, copper solid solution and titanium solid solution. When the welding energy was increased to 2000 J, the joint interface microstructure was composed of CuZn, Zn15Ti compound and copper solid solution. In comparison, Cu/Ti joints welded with a Zn interlayer in-between displayed the maximum shearing force about 33.5% greater than those of joints without a Zn interlayer.

Catalytic activity of nickel–copper powder alloys in the processes of electrochemical hydrogen evolution in alkaline solution and ethanol alkaline solution

Ni 93 Cu and Ni 82 Cu (at%) alloys were synthesized by the method of combined chemical reduction of Ni(II) and Cu(II) with hydrazine hydrate. These alloys consist of crystalline phases of nickel, solid solution of copper in nickel. Determination by the “capacitive method” of the electrochemically active surface area of working graphite electrodes with “catalytic inks” containing Ni 93 Cu and Ni8 2 Cu powders showed that it is 4 and 20 % larger than for nickel powder, respectively. It was found that powder alloys Ni 93 Cu and Ni 82 Cu are applicable as catalysts for the electrochemical process of hydrogen evolution in alkaline solutions and alkaline ethanol solution. It was determined that the catalytic activity of Ni82Cu powder alloy in the process of hydrogen evolution in the alkaline ethanol solution is higher than for nickel and Ni 93 Cu powders. The catalytic ability of the Ni 82 Cu powder alloy during cycling for 25 cycles practically does not change, in contrast to Ni and Ni 93 Cu.

МОРФОЛОГИЯ И СОСТАВ ИМПАКТНЫХ ПРОДУКТОВ

The object of study is the products of the Zhamanshin crater: tektites – irgisites, subtektites, zhamanshinites. The features of morphology and the compositions of products were determined. In the distribution of rare earth elements of irgisites Eu and Ce anomalies appeared. The crystallized components of jamanshinite consist of phayalite, ferrosilite, magnetite. Large inclusions of zhamanshinite are represented by a solid solution of copper and boron, small ones by galenite with impurities of iron and tungsten. Among the accessor minerals of subtektites, xenotime, iocyte, coesite were found. The proximity of the mineral compositions of subtektites and a number of comets was confirmed.

Mechanical properties and failure analysis of laminated magnesium-intermetallic composites

<abstract> <p>Laminated Mg-intermetallic composites were successfully fabricated by reaction synthesis in vacuum using 1 mm thick magnesium sheets and 0.25 mm thick copper foils. The final microstructure consisted of alternating layers of a hypoeutectic alloy containing crystals of CuMg<sub>2</sub> and eutectic mixture of CuMg<sub>2</sub> and solid solution of copper in magnesium and unreacted magnesium. The mechanical properties and fracture behavior of the fabricated composites were examined under different loading directions through compression, three-point bending and impact tests. The results indicated that the composites exhibited anisotropic features. The specimens compressed in the parallel direction failed by cracking along the layers of intermetallics and buckling of magnesium layers. The specimens compressed in the perpendicular direction failed by transverse cracking in the intermetallic layers and fallowing catastrophic cracking inclined about 45° to the interface of both intermetallic and magnesium layers. The flexural strength of the composites was higher in perpendicular than in parallel direction. When the load parallel to the layers was applied, the failure occurred by cleavage mode showing limited plastic deformation. When the load perpendicular to the layers was applied, the failure occurred by transverse cracking of the intermetallic layers and gradual cracking of the Mg layers. The Charpy-tested samples showed the same fracture behavior as the bend-tested specimens, which indicated that the same mechanisms operated at both high impact rate and low bending-test rate.</p> </abstract>

Mechanism of Modification of Strength/Stress–Relaxation Properties Induced by Low–Temperature Annealing in Solid–Solution Copper Alloys

Mechanism of Modification of Strength/Stress–Relaxation Properties Induced by Low–Temperature Annealing in Solid–Solution Copper Alloys

Effect of Plastic Deformation Modes on Dislocation Evolution in Solid–Solution Copper Alloys

Effect of Plastic Deformation Modes on Dislocation Evolution in Solid–Solution Copper Alloys

Structural and Phase Transformations in a Coating Based on Copper and Zinc Particles Deposited by Gas Dynamic Spraying

The structure of a coating based on a mixture of particles of Cu and Zn deposited by the method of gas dynamic spraying is studied. An x-ray diffraction analysis and a microscopic spectrum analysis are used to determine the structure and the elemental composition of the coating. Development of diffusion after the formation of the coating is shown to yield a solid solution of copper and zinc in it. The phase composition of the coating after the heat treatment (a hold at 405 – 415°C) is shown to change for intermetallic compounds and a solid solution of zinc in copper.

Interaction of edge dislocation with copper atoms in an aluminum crystal

In this work, the interaction of the moving edge dislocation with obstacles in form of copper atoms is studied using the molecular dynamics simulations. The samples are aluminum monocrystals of 52 × 60 × 15 nm3 with axes oriented along directions [110], [111], [112]. The structure of copper solid solution is reproduced with following procedure: aluminum atoms are randomly selected and replaced by copper atoms. The concentration of copper atoms varies from 0.25% to 1%. The dislocation movement occurs under action of shear deformation. It is found that zones with a low concentration of copper atoms only slow down dislocation in an aluminum matrix, and the zones with a high local concentration of copper atoms not only produces stronger resistance to dislocation movement, but also they cause the change in the slip plane of the dislocation segment. When a significant part of a dislocation line moves to a neighboring slip plane, the complete transition of the dislocation to this slip plane can occur. It is also noted that such transitions of dislocation segments from one slip plane to another are accompanied by the formation of vacancies. Also the maximum value of the shear stress σxy is estimated-its value is approximately 250 MPa.

Закономерности формирования структурно-фазовых состояний биметаллических наночастиц Ag-Cu, полученных электрическим взрывом двух проволок

In present work we observed structural phase state formation of Ag-Cu nanoparticles by electrical explosive of wires. We observed the formation of bimetallic nanoparticles with a number average size of 75 ... 82 nm by synchronous and nonsynchronous electric explosion of wires. The phase composition of the samples is represented by phases based on solid solutions of copper and silver. The results of the studies allow us to conclude that, using electric explosion of copper and silver wires, bimetallic Ag-Cu nanoparticles with different mass ratio of metals can be obtained.

Effect of Kinds of Alloying Elements in Solid–Solution Copper Alloys on Dislocation Evolution

Effect of Kinds of Alloying Elements in Solid–Solution Copper Alloys on Dislocation Evolution

Microstructural and Mechanical behaviour of Nickel Aluminum Bronze alloys

The present investigation reports on microstructure and mechanical characterization of permanent and shell moulded Nickel Aluminum Bronze alloy Castings (NAB) (AB2) melted in Medium Frequency coreless Induction furnace. The mechanical properties studied consisted of Tensile strength, Yield Strength, ductility on one hand, Optical microscopy and grain size measurements on the other. Effect of zirconium addition on the microstructure and mechanical characteristics of Permanent and shell moulded castings have been studied. The results of this investigation reveal that microstructures consisted of dispersed particles in the matrix of copper solid solution both in permanent and shell moulded castings. Shell moulded castings exhibited extensive grain refinement compared to Permanent moulded castings. Very high values of Tensile Strength, Yield strength and Elongation values are obtained for the Nickel Aluminum Bronze alloys. Shell moulded castings have exhibited superior mechanical properties than Permanent moulded castings in all the characteristic/property values obtained.