Copper Alloys Research Articles

Semantic Representation of Low‐Cycle Fatigue Testing Data Using a Fatigue Test Ontology and ckan.kupferdigital Data Management System

Addressing a strategy for publishing open and digital research data, this paper presents the approach for streamlining and automating the process of storage and conversion of research data to those of semantically queryable data on the web. As the use case for demonstrating and evaluating the digitalization process, the primary datasets from Low‐Cycle Fatigue (LCF) testing of several copper alloys are prepared. The Fatigue Test Ontology (FTO) and ckan.kupferdigital data management system are developed as two main prerequisites of the data digitalization process. FTO has been modeled according to the content of the fatigue testing standard and by reusing the Basic Formal Ontology (BFO), Industrial Ontology Foundry (IOF) core ontology, and Material Science and Engineering Ontology (MSEO). The ckan.kupferdigital data management system was also constructed in such a way that enables the users to prepare the protocols for mapping the datasets into the knowledge graph, and automatically convert all the primary datasets to those machine‐readable data which are represented by the Web Ontology Language (OWL). The retrievability of the converted digital data was also evaluated by querying the example competency questions, confirming that ckan.kupferdigital enables publishing open data that can be highly reused in the semantic web.This article is protected by copyright. All rights reserved.

Role of layer thickness on the damage mechanism in the LPBFed copper alloy

Role of layer thickness on the damage mechanism in the LPBFed copper alloy

Cauldrons of Bronze Age nomads reveals 2700 year old yak milk and the deep antiquity of food preparation techniques

Cauldrons, vessels that are simultaneously common and enigmatic, offer insights into past cultural and social traditions. While assumed to possess a special function, what these cauldrons contained is still largely mysterious. These vessels, such as those made from bronze or copper alloys, function as reservoirs for ancient organics through the antibacterial qualities provided by the metal surfaces. Here we show, through protein analysis, that cauldrons from the Final Bronze Age (ca. 2700 BP) were primarily used to collect blood from ruminants, primarily caprines, likely for the production of sausages in a manner similar to contemporary practices in Mongolia’s rural countryside. Our findings present a different function from the recent findings of cooked meat in copper-alloy vessels from the northern Caucasus 2000 years earlier, exposing the diversity in food preparation techniques. Our secondary findings of bovine milk within the cauldron, including peptides specific to Bos mutus, pushes back their regional domestication into the Bronze Age.

Fatigue Behaviors and Dislocation Evolution of Copper and Aluminum Alloy

Face‐centered cubic (FCC) metals are widely used in the field of structural materials due to their excellent mechanical properties, and their fatigue behaviors have always been a focus of attention. Herein, 1060 aluminum alloys with different processing states and copper are selected to study the high cycle fatigue performance at room temperature and high temperature. The fracture morphology and dislocation evolution are characterized through characterization methods such as scanning electron microscope and transmission electron microscope. Based on the research, the main movement mode of dislocations (plane slip or wavy slip) are influenced by stacking fault energy (SFE), which further has a significant impact on fatigue performance. When the SFE of the FCC metal is higher, wavy slip dominates and the material is sensitive to temperature changes; on the contrary, during cyclic loadings, metal with lower SFE is dominated by plane slip, due to the reversibility of plane slip, the damage to the material with low SFE under fatigue loading is more uniform.

Lost-wax casting: A widespread technique to produce copper alloy adornments in Atlantic Europe since the mid-second millennium BC

Lost-wax casting is a metalworking technique that has long been regarded as an innovation imported from the eastern Mediterranean and only widely used in Western Europe since the Late Bronze Age. We now have evidence that this technique was in fact largely in use from the Middle Bronze Age onwards for the production of copper alloy adornments in the Atlantic area. Along with palstaves, these objects are the most abundant in Atlantic hoards from the 15th to the 13th centuries BC. Thanks to detailed morphological and technological study, combined with an experimental approach and analysis of their elemental composition, we can propose new chaînes opératoires for the manufacture of massive annular bracelets with geometric decoration.

Effect of aging temperature on microstructure and properties of cold-rolled Cu-Ni-Si alloy

The aging process plays a pivotal role in shaping the microstructure of Cu-Ni-Si alloys, a typical kind of precipitation-strengthened Cu alloy. This process significantly affects both the mechanical and electrical properties of the final Cu alloy strips. In this study, Cu-Ni-Si alloy sheets underwent a 90 % reduction through cold rolling at room temperature, followed by heat treatment at temperatures ranging from 400 to 650 ℃. A comprehensive investigation was conducted into how cold rolling deformation and the aging process affect the alloy's microstructure, as well as its mechanical and electrical properties. The analysis was performed using a scanning electron microscope equipped with a backscattered electron diffraction system (SEM-EBSD), complemented by transmission electron microscopy (TEM). The findings revealed that recrystallization and precipitation occurred concurrently and were both enhanced by higher temperatures and prolonged heat treatment durations. However, recrystallization at elevated temperatures has a marginal impact on enhancing electrical conductivity and results in a significant reduction of mechanical properties. In contrast, alloys preserving the deformed microstructure benefit from multiple strengthening mechanisms, including precipitation, dislocation, grain boundary, and texture strengthening. This study offers quantitative insights into the precipitation and recrystallization behaviors of Cu-Ni-Si alloys, contributing significantly to a deeper understanding of the mass production of high-performance copper alloys.

Numerical study of electroconductive non-Newtonian hybrid nanofluid flow from a stretching rotating disk with a Cattaneo–Christov heat flux model

Motivated by emerging technologies in smart functional nanopolymeric coating systems in pharmaceutical and robotics applications, the convective heat transfer characteristics in swirl coating with a magnetic hybrid power-law rheological nanofluid polymer on a radially stretching rotating disk are examined theoretically. An axial magnetic field is imposed. Copper (Cu) and aluminium alloy (AA7075) nanoparticles with sodium alginate (C6H9NaO7) as a base fluid are considered, and a hybrid volume fraction model is deployed. A non-Fourier (Cattaneo–Christov) heat flux model is deployed to inspire thermal relaxation impacts absent in the classical Fourier heat conduction formulation. Through similarity proxies and the Von Karman transformations, the partial derivative systems of equations with associated boundary constraints are reduced to a system of derivative boundary value problems, which is solved numerically via the weighted residual method with an integral Galerkin scheme, executed in the MAPLE symbolic software. Validation with special cases from articles is captured. The computations revealed that radial, tangential and axial velocity are depleted, whereas temperature is enhanced with increasing magnetic parameter ( M). High thermal transfers are obtained for the hybrid nanofluid relative to the AA7075 alloy nanofluid. A strong increment in temperature is also produced with a greater thermal relaxation effect.

Study on seawater corrosion resistance of copper alloy

Abstract The Marine environment is a very complex and corrosive environment. Marine corrosion environment can be generally divided into Marine atmospheric environment and seawater environment. Because the seawater is rich in a variety of free ions mixed with corrosive media, the main component is sodium chloride, in addition to containing magnesium, potassium, iodine, bromine, and other elements of salt, which has strong corrosion to metal materials, if serious, it will cause safety accidents. Therefore, ensuring the effectiveness of the anticorrosion system is very important for the safe and reliable operation of the offshore platform. pulse plating is used and the metal nickel coating and metal nickel-chromium coating are prepared to analyze the microstructure and corrosion resistance of each film layer. From the macroscopic, it can be found that three coatings have more or less corrosion phenomenon, there is obviously no nickel-chromium and nickel layer on the surface of nickel-chromium corrosion defects, and through scanning electron microscopic observation, microscopic level nickel chromium corrosion after corrosion phenomenon is the least of three layers, which suggests that nickel chromium seawater corrosion resistance is strong. The three layers are then electrochemical corroded to study the corrosion resistance of the three layers. The results show that the corrosion resistance of the nickel-plated layer, nickel-chromium coating, and nickel-iron chromium coating prepared in the copper substrate is improved successively, which shows the influence of different membrane elements on the corrosion resistance of copper substrate against seawater medium. Although the composition parameters of the various membrane layers vary, they experience the same corrosion mechanism-pitting; Nickel chromium and chromium, iron and other atoms are present in the nickel matrix in the form of solid solution and finally form the solid solution alloy coating. For nickel-chromium coating, the content of iron and chromium in the surface layer has a certain influence on the corrosion resistance of the metal coating. The electrochemical parameters of nickel plating are studied separately, and the comparison with the nickel-chromium alloy coating and the coating is conducted. The equivalent circuit is fitted and determines the largest impedance value and the largest phase Angle among the three membrane layers, which finally has the strongest seawater corrosion resistance.

Experimental Study of Chalconatronite: From Its Identification to the Treatment of Copper Alloy Objects

On the occasion of the reopening of the Dobrée Museum (Nantes, France), two statuettes of Egyptian origin, representing Harpocrate and Isis, were studied to shed light on the presence of the blue-green efflorescence on their surface. The efflorescence on the Harpocrate statuette was identified as being chalconatronite, while that which was present on the Isis statuette corresponded to sodium copper formate/acetate, probably due to the evolution of chalconatronite in an environment containing VOCs. The efflorescence appeared to be sensitive to the cyclic variation in relative humidity whereas it seemed stable. An experimental curative treatment to halt the reappearance was carried out. A series of pure water baths extracted a significant quantity of sodium. The treatment appeared effective and reduced the risk of a recrudescence of the efflorescence for both statuettes. However, when the efflorescence was dissolved on the Isis statuette, other compounds appeared to react with water, leading to acidification and a potential reaction with the lead in the alloy. A layer of lead carbonate/acetate on the surface appeared. The objects were then dried and protected with a highly concentrated acrylic varnish. They are currently being monitored to identify any new efflorescence that may appear during display.

Effects of CuCr1Zr contamination on the tensile properties and microstructure of stainless steel 316L produced via laser powder bed fusion

AbstractCopper contamination has a negative effect on the tensile properties of certain stainless steel grades due to a weakening of grain boundaries via liquid metal embrittlement. This is especially problematic given current trends in laser powder bed fusion (L-PBF) that elevate contamination risks, such as multi-material processing or the use of recycled materials. As such, it is critical to establish composition limits for use in standard specifications. This study investigates the changes in tensile properties and cracking behavior in stainless steel alloy 316L contaminated with copper alloy CuCr1Zr at concentrations of 0–10 particle percent (pt.%) in horizontal, diagonal, and vertical build orientations. It is found that microcracks are already present at 1 pt.% Cu alloy and increase in density with contamination. The cracks are generally vertically oriented along columnar grain boundaries and are associated with high local Cu content, thus exacerbating the anisotropy of the as-built material. The contamination decreases the elastic modulus, yield strength (YS), ultimate tensile strength (UTS), and uniform elongation, eventually transitioning from ductile to brittle fracture modes. The build orientation relative to the tensile loading axis is shown to be a critical design parameter due to the preferential crack initiation and growth direction. The fracture surfaces at 10 pt.% contamination show regularly spaced, smooth brick-like cleavage patterns that correspond to the columnar grain dimensions. Even so, the measured YS and UTS exceeded the ASTM F3184-16 standard for CuCr1Zr contaminations up to 5 pt.%. As a conservative limit, it is proposed that a maximum content of 1 wt% Cu be specified for L-PBF SS316L.

Progressive effect of dual-hybridization in friction stir welding by ultrasonic vibration and resistive heating for joining dissimilar material Al6063 aluminium alloy and C26000 copper alloy

In the world of disruptive technology, Al–Cu joints are quite in demand for electric vehicle batteries and other ion battery applications. Fusion welding is the less preferred method due to its many disadvantages; friction stir welding has the potential to become a sustainable process for producing a sound dissimilar Al–Cu joint. A study of multiple hybridization to the Friction Stir Welding (FSW)was made by utilizing two different energy sources of ultrasonic energy and electric current. The improvement is the property by different combination of the hybridization studied for utilizing the multiple hybridization technique to the FSW process for improving the weld efficacy and defects free weld even in case of dissimilar joints. Mechanical properties obtained by varying the process parameters have been studied and compared. Three process parameters have been selected including ultrasonic energy (10 KHz), electric current (75–125 Amps), rpm (400–600 rpm) and transverse tool rate (30–50 mm/min). A remarkable improvement in the mechanical property has been monitored by adding electric current to the UAFSW. Similar optimistic results in the improvement of the property have been found by adding Ultrasonic energy to RHFSW. The comparative study in the mechanical property had been presented to explain the improvement in the weld efficacy.

Assessing Tensile Strength and Electrical Conductivity of Friction Stir-Welded Joints of Copper and Aluminum Alloys

Dissimilar aluminum joints have widespread applications across various industries, including the electronics and automotive sectors, owing to their unique combination of advantages, including reduced density and enhanced mechanical properties. These characteristics make them an innovative solution for multi-material processing challenges presented in the engineering industry. This article focuses on Friction Stir-Welded butt joints made using a weld–flip–weld approach between aluminum AA6061-T6 and pure copper C11000, exploring the effects of varying rotational speeds (1000, 1200, and 1400 RPM), offsets (0 and 1 mm) in the joint soundness, mechanical strength, and electrical conductivity. The welds were evaluated using non-destructive testing with phased-array ultrasound and tensile testing. Additionally, the electrical conductivity was measured to assess their response to electrical currents. The findings reveal a significant correlation between joint efficiency and electrical conductivity, with the highest values corresponding to a weld executed with a rotational speed of 1400 rpm, traverse speed of 40 mm/min, and 1 mm offset towards the aluminum, achieving the highest joint efficiency, reaching a joint efficiency of approximately 75% and 82.42% of the IACS for electrical conductivity.

Enhanced corrosion protection of copper alloy in 2.0 M HNO3 solution using expired solo sept, slim-lax and well derm drugs

Three expired drugs, Solo Sept (SS), Slim-lax (SL), and Well Derm (WD), have been tested as corrosion inhibitors for corrosion of copper alloy (C10100) in 2.0 M HNO3 solution. Three experimental methods such as weight loss measurements, potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) were applied in this study. These expired drugs function as effective inhibitors, according to the experimental findings. The efficacy of inhibition rises with increasing drug concentration and falls as temperature rises. From PDP, the examined drugs that worked as mixed-type inhibitors. EIS measurements showed a remarkable increase in the charge transfer resistance and decreases in the capacity of the double layer of the corroding copper in 2.0 M HNO3 solution with increasing drug concentration. The inhibition power of these drugs was interpreted in term of its adsorption on the C10100 surface according to Langmuir isotherm. The inverse effect of temperature on drug efficiency as well as the small negative values of ∆G°ads (-20.84, -20.52 and -20.51 kJ/mol) for SS, SL and WD respectively, supports the physical adsorption of drugs on the C10100 surface. All results showed consistency with IE order (SS > SL > WD). The adsorption thermodynamic functions were estimated. The corrosion inhibition performance of SS was confirmed through SEM (scanning electron microscope) and FTIR.

Design and optimization of a castability test for copper alloys applied to plaster moulds

The paper deals with the design and execution of the test of the castability into preheated plaster moulds. Castability is an important parameter for the evaluation of foundry alloys. When the metal does not run, it usually causes an irreparable defect in the casting. Therefore, it is necessary to verify this technological property correctly for different types of moulds. The castability test for plaster moulds and bronze is not defined, therefore The Vertical Bar Test was adopted, subsequently modified, and applied to plaster moulds. The models are made of wax and the plaster moulds are made according to the manufacturer's prescription and heated to a predetermined temperature. Copper alloy specifically CuSn10 was selected as the alloy to be investigated.The aim of the experiment is to correctly set up and observe the parameters and the method of performing the castability test using gravity casting technology in plaster moulds. It is assumed, as the casting temperature increases, the run-in length of the metal alloy will increase. An important goal is to obtain relevant results, as many variables affect the progress of the test and so there is a risk of error. Due to the time-consuming nature of producing a real disposable model and mould, any failure to succeed would have an economic impact on the foundry, affecting the price of castings. The new method for evaluating castability in plaster moulds can be applied to other types of alloys when temperature changes occur.

Compositional Design and Thermal Processing of a Novel Lead-Free Cu–Zn–Al–Sn Medium Entropy Brass Alloy

In the current work, a novel medium entropy copper alloy was designed with the aim of avoiding the use of expensive, hazardous or scarce alloying elements and instead employing widely available and cost-effective alternatives. In order to investigate this unknown region of multicomponent alloy compositions, the thermo-physical parameters were calculated and the CALPHAD method was utilized. This led to the design of the Cu50Zn25Al20Sn5 at. % (Cu53.45Zn27.49Al9.08Sn9.98 wt. %) alloy with a relatively low density of 6.86 g/cm3 compared with conventional brasses. The designed alloy was manufactured through vacuum induction melting, producing two ingots weighing 1.2 kg each, which were subjected to a series of heat treatments. The microstructural evolution of the alloy in the as-cast and heat-treated conditions was assessed through optical and scanning electron microscopy. The hardness of the as-cast and heat-treated alloy at room temperature was also studied. The alloy was characterized by a multiphase microstructure containing a major Cu-rich (Cu–Zn–Al) matrix reinforced with a secondary Zn-rich (Zn–Cu) phase and pure Sn. In terms of mechanical properties, the developed alloy exhibited high hardness values of roughly 378 HV0.2 and 499 HV0.2 in the as-cast and heat-treated conditions, respectively.

Express Method for Assessing Performance of Lubricant Compositions Containing Nano-Additives Used for Wheel-Rail Pairs.

An express method for assessing the effectiveness of lubricating compositions with nano-additives of various chemical compositions is proposed, and a joint analysis of experimental data on the changes in the value of wear and the level of damage to the surface layers of metallic friction pairs was performed. The variation in the current relative hardness of the sample's surface, the variation in the current relative material damage level, the current value of wear, and the current level of the coefficient of friction were chosen as the key parameters to conduct a performance assessment. The level of material damage in the contact zone was determined using the parameters of the statistical law of hardness value scattering. Based on an analysis of data in the literature, it was observed that the structural changes occurring in metallic materials during long-term, cyclic, static, and frictional loading are correlated with changes in the statistical characteristics of the hardness scattering results. An experimental substantiation of the proposed method was carried out for steel-sliding friction pairs using lubricating compositions based on Greaseline Lithium BIO Rail 000 oil manufactured by AIMOL with nano-additives of copper, magnesium and aluminum alloys, graphite, and two grades of medium-carbon steel. According to the system of indicators presented in this research, the greatest efficiency (in terms of increasing the wear resistance of friction steel pairs) was achieved with lubricating compositions including nano-powder additives made of steel, which have lower hardness. For the friction experiments, where the determining factor was abrasive wear, such lubricants ensured minimal damage and wear to the friction surface, while the value of the friction coefficient was maintained at a level that is optimal for wheel-rail friction pairs.

Tribological Properties and Wear Mechanisms of Laser Cladded Cu–Mo Coatings at 25–500 °C

Abstract Surface modification is the major means to improving the wear resistance of copper alloys. In this study, Cu–Mo coatings were prepared on Cu–Cr–Zr alloy by laser cladding, and the high-temperature tribological properties against 7075 aluminum alloy were explored. The results show that the coatings are a two-phase structure of Mo encapsulated in Cu-mesh. The hardness and resistivity of the coatings are 61–73 Hb and (3.2–6.3) × 10−8 Ωm, respectively. The wear resistance of the coatings is determined by the hardness, which is related to the Mo content at lower temperatures, and it is controlled by the tribo-oxides layer composed of copper and molybdenum oxides at higher temperatures. As the temperature increases, the main wear mechanism of the coatings changes from abrasive wear to adhesive wear.

Modificated microstructure and enhanced mechanical properties of Cu-Sn-P alloy with rare earth La addition

Rare earths are often added to copper alloys as trace alloying elements to modify the structure and improve related properties. In this study, the Cu-7.8Sn-0.16 P and Cu-7.8Sn-0.16 P-0.15La alloy strips were fabricated through full-chain process of vacuum casting, cold rolling, intermediate annealing, cold rolling and low temperature annealing process. Then, the distinctive microstructure features and mechanical properties of Cu-7.8Sn-0.16 P and Cu-7.8Sn-0.16 P-0.15La alloys were comprehensively analyzed in special view of rare earth affected phase types and property evolution. The results indicate that the addition 0.15 wt% La has effectively refined the dendrite segregation and dispersed the microporosity. Specifically, La combines with P and form a stable and dispersed micron sized LaP2 intermetallic compound, which replaces the low melting point (α+δ+Cu3P) ternary phase in the La-free alloy. Furthermore, a new nanoscale La(Cu2P)2 precipitated phase is characterized in the Cu-7.8Sn-0.16 P-0.15La alloy during low-temperature annealing process. As well, the tensile strength of Cu-7.8Sn-0.16 P-0.15La strips display notable increase to 915 MPa from 834 MPa of Cu-7.8Sn-0.16 P after low-temperature annealing. Such increase in tensile strength is attributed to the formation of La-containing phase of varied sizes in the Cu-7.8Sn-0.16 P-0.15La alloy, where the nano scale La(Cu2P)2 precipitated phase makes the most significant contribution.

In-situ construction of epitaxial phase for boosting zinc nucleation on three-dimensional interface

Interface modification of zinc (Zn) metal anode with conductive three-dimensional (3D) structure is widely utilized in zinc ion batteries. However, the uniformity of zinc nucleation on surface microstructure is rarely investigated which exacerbates the tip effect and raises unstable risk. Herein, a strategy via the initial copper (Cu) alloying and following sulfurization treatment is reported to accomplish boosted uniform nucleation of zinc on the modified layer with dense microstructures. This epitaxial sulfide phase not only improves the wetting area to revitalize the microstructural surface, but also forms a bifunctional zincophilic Cu2S/CuZn alloy interface layer, which combines the merits of guided local ions diffusion and improved zinc nucleation environment. As a result, a homogeneous growth of zinc on the 3D structural substrate can be realized, and cycling stability of the achieved Cu2S/CuZn electrode with a practical capacity of 1 ​mAh cm−2 under 1 ​mA ​cm−2 or amplified current density of 10 ​mA ​cm−2 is significantly enhanced. This work provides an epitaxial strategy in constructing a bifunctional zincophilic interface layer for boosting zinc nucleation, and offers a new perspective on the modification of 3D surface structure for stabilization of zinc anode.

Strategy for co-enhancement of corrosion resistance-strength of Cu-7Ni-3Al-1Fe-1Mn alloy: Rare earth Sm microalloying

Both high strength and superior corrosion resistance are necessary for Cu-Ni alloys when serving in marine engineering. We discover that the corrosion resistance and strength of Cu-7Ni-3Al-1Fe-1Mn alloy can be enhanced via rare earth Sm microalloying. When Sm content is 33 ppm, the alloy exhibits not only the lowest corrosion rate, which is 40% lower than the Sm-free alloy, but also the maximum tensile strength, which is 6% higher than the Sm-free alloy. After alloying 33 ppm Sm, the average grain size of Cu-7Ni-3Al-1Fe-1Mn alloy is reduced by 42%, from 205 μm to 118 μm. In addition, CuSm phase and (Sm2S3-Al2O3) composite phase appear in the alloy after alloying 33 ppm Sm. The improvement of corrosion resistance is primarily due to the formation of Cu-Sm precipitates, leading to a positive shift of the corrosion potential. Further analysis indicates that the increased strength can be mainly attributed to grain refinement and the formation of Sm-S precipitations. This work promotes a new method for enhancing the strength and corrosion resistance simultaneously of copper alloy.