Bronze Materials Research Articles

Corrosion and Protection of Chinese Bronze Relics: A Review

The corrosion problem affecting ancient Chinese bronze relics and the protective measures required post-excavation are crucial for the study of historical cultural heritage and for ensuring heritage revitalization and sustainable development. This work includes a statistical analysis, clusters information, and thoroughly examines international research on bronze relic corrosion and protection. It delves into the timeline and trends of research, the main countries leading the research efforts, the research content, and the relationships between these factors. A comprehensive review is provided on the corrosion principles, materials, detection methods, and protection techniques for bronze. The study explores the corrosion principles and processes of bronze from a materials science perspective both before and after excavation. It summarizes non-destructive detection methods and examines specific factors that influence corrosion. Furthermore, the article reviews current corrosion protection methods for bronze and related protection materials, including commonly used strategies such as surface corrosion inhibitors and organic resin coatings for protection. It also discusses the potential application of advanced corrosion protection methods in the realm of metal materials in recent years to safeguard bronze. Proposing innovative solutions, the study suggests the possibility of constructing biomimetic superhydrophobic surfaces to create a barrier isolating humid air from contacting bronze materials, thereby reducing the adhesion of corrosive media to the substrate and significantly diminishing the likelihood of corrosion. In conclusion, the article looks towards the future, considering the challenges and potential development directions for the corrosion protection of bronze and related protection materials.

CsxWO3 films with excellent infrared shielding ability and high visible light transmittance prepared via magnetron sputtering

Caesium tungsten bronze materials are widely used in various applications, such as architectural glass, medicine, insulation coating and textile fibre, owing to their excellent mechanical, optical and thermal properties. In this study, a caesium tungsten bronze (CsxWO3, x = 0.3–0.32) target with a relative density of 99.63 % and uniform microstructure was successfully prepared via hot-pressing sintering. CsxWO3 films were deposited on a quartz glass substrate via magnetron sputtering, and the mechanisms and effects of the substrate temperature and oxygen flow rate on the phase structure, microstructure and optical properties of CsxWO3 films were investigated. When the substrate temperature increased, the crystallinity and oxygen vacancy concentration of the CsxWO3 film improved. Consequently, the visible light transmittance of the film decreased, whereas the infrared blocking rate considerably increased, reaching up to 93.877 %. With the increase in the oxygen flow rate, the visible light transmittance exhibited an increasing trend, reaching a maximum value of 84.319 %, whereas the infrared blocking rate remained relatively stable. We successfully fabricated CsxWO3 films possessing a visible light transmittance of 66 % and infrared blocking rate of 94.97 % under the conditions of a substrate temperature of 300 °C and an oxygen flow rate of 2.5 sccm. Our study offers a method for the large-scale production of CsxWO3 films, which are excellent infrared shielding materials, rendering a substantial contribution to global energy conservation and emission reduction.

Investigation of laser-material interaction in picosecond single-point laser ablation of bronze

Comprehending the laser ablation mechanism is fundamental in determining how diverse laser parameters affect the quality of the ablation process. A finite difference model was developed in this study to investigate the ablation depth and temperature distribution in picosecond ablation process. The investigation involved conducting single-point laser experiments on bronze material using an ultrashort pulse laser with a pulse duration of 12 ps. The experiments were carried out with varying numbers of pulses, ranging from 1 to 80 pulses. The calculated depths of ablations were compared with experimental results. The variation of the ablation mechanism on the workpiece's surface during laser radiation was also investigated. The model established the laser-material interaction mechanisms under different incident pulses. The ionization temperature and ablated material temperature during laser processing are also determined. The results show that for the number of pulses higher than 10, the laser-material interaction changes from Multi-Photon Ionization to ablation, while in lower numbers, there are no effects of thermal damages adjacent to the laser points. The relationship between variations in the ablation depth and changes in the incidence angle was also investigated. As the incidence angle increases, the removal mechanism changes from MPI to the thermal.

Investigation of scanning strategies on performance of nanosecond and picosecond laser volume ablation of bronze

Understanding of laser volume ablation performance in different scanning strategies is indispensable for practical applications. This study investigates the influence of different laser scanning parameters on the performance of volume ablation of bronze material. The results reveal significant differences between the selected pulse durations of 16 ns (ns) and 12 picoseconds (ps), despite both using an identical maximum average power of 40 W. In both cases, increasing the scanning area resulted in a proportional increase in ablation depth. Compared to the ns-laser, the ps-laser exhibited significantly lower ablation depths, approximately 35 % to 40 % less, with consistent performance across different scanning directions. Surface topography analysis showed that scanning direction played a crucial role in determining the final surface quality, with a nearly 50 % improvement observed with the mixed scanning strategy. With the ps-laser, expanding the scanning area led to reduced surface roughness, primarily due to pure ablation and minimal surface re-melting. Further strategies, such as interlace and halftone were also explored. Adjusting the line delay time was also considered, with longer delays potentially resulting in deeper ablation and slightly improved surface roughness. The study also investigated the pitting phenomenon, which was found to be intensified around contour edges. Notably, pitting was more pronounced in ns ablation during the initial scanning layers, while in ps ablation, pitting distribution intensified with an increase in scanning layers and ablation depth.

Analysis of elastic stresses in rotating cylinders made of Titanium and Bronze materials

ABSTRACT This study analytically investigated elastic stress distribution in rotating cylinders made of Titanium and Bronze material. The Von Mises yield criterion was applied under the assumption of plane strain conditions. The modelling process considered that the disc material remains unaffected by temperature variations. The thermal stresses of a thin circular disc are being studied. The determined temperatures are close to the maximum and minimum temperatures at which the material can work. The numerical analysis is one, and the results are depicted as a whole with graphs. This study also examined the changes in the temperature distribution on the stress distribution. At the end of the study, it was determined that the stresses occurring in the titanium material cylinder were higher than the bronze disc, and the pressures were inversely proportional to the increase in the grading parameter in the cylinders. Additionally, the ANSYS finite element program was utilised for validation.

Mechanism of corrosion behavior between Pb-rich phase and Cu-rich structure of high Sn–Pb bronze alloy in neutral salt spray environment

The corrosion behavior and corrosion mechanism of the Pb-rich phase and Cu-rich structure of the Sn–Pb bronze alloy in a high-chloride and high-humidity environment were studied. The phase composition of the bronze alloy was analyzed by observing the metallographic and EPMA element distribution, the potential of the microstructure was characterized by SKPFM. The corrosion products and morphology results after electrochemical and neutral salt spray tests were analyzed. The results showed that the matrix structure of bronze material was composed of Pb-rich phase and Cu-rich structure (α(I) phase and (δ+α(II)) eutectoid). During the corrosion process, the rich Pb phase preferentially corroded as the anode and diffused towards the surroundings, while the rich Cu structure served as the cathode. In the rich-Cu structure, compared with δ, the α phase was used as the anode. The corrosion products on the alloy surface mainly included Cu2O, PbCO3, and Cu2(OH)3Cl. As the corrosion gradually deepened along the depth of α phase, the galvanic couple effect between α phase and δ phase and the “oxygen concentration cell” effect gradually increased.

Manufacturing Techniques of Ancient Forged High-tin Bronze Wares from Archaeological Sites in Bagan, Myanmar

Bronze wares made with forged high-tin bronze technology were first produced in the Persian region of the Orient, gradually brought to India and then to China and the Korean Peninsula. By scientifically analyzing bronze artifacts of Myanmar, which is located halfway between Persia and Korea, it is possible to confirm the trade and the propagation route of technology at the time. This study scientifically analyzed bronze artifacts excavated from the Bagan ruins in Myanmar to identify the manufacturing technology. Forged high-tin bronze wares in Bagan Dynasty are with alloy compositions Cu-Sn. Composed of Cu-Sn only were manufactured by alloying Cu with Sn in a ratio of 76 wt% and 24 wt%, which is a relatively high tin content. High-tin bronze wares composed of Cu-Sn were manufactured with the bronze material of an alloy of Cu and a large amount of Sn by hot working (forging) and finished by quenching. The microstructure indicates temperatures at which the quenching was performed and various microstructures that occur in different temperature ranges are observed such as β (M), γ phase, δ phase as well as primary crystals, α phase. The presence of different microstrucures suggests multiple high-tin bronze wares were quenched at a wide range of temperatures. The non-metallic inclusions of the bronze wares contain sulfur, which indicates with high possibility that the copper provided as the raw material was extracted from copper ores containing sulfur.

Highly processed bronze jewelry and ornaments in the Vértesszőlős find ensemble

Vértesszőlős was a populated area during the broad period of the Bronze Age. Artefacts from different cultures, and among them many bronze objects were found. Most are ornaments, but tools and weapons have also been unearthed. Jewellery and dress ornaments are found in many areas, and the examination provides an opportunity to compare regions, ages, and customs. Several stud ornaments and sporadic stud fragments were found during the excavation. Making studs requires careful elaboration and production. In general, it was stated that they were made of an alloy with a low and average tin content (3.5 -6 w% tin), which is malleable and easy to deform plastically. The morphology of the inclusions also suggests a high degree of plastic deformation. Due to the thin bronze material, the objects are subjected to solid corrosion effects, necessitating a detailed microstructural examination to examine the other constituents. The spiral beads require similarly careful elaboration, two of which were selected for parallel examination. A similar test protocol had to be used to determine the effect of corrosion. A slightly higher tin content and a more minor total deformation were found. The objects are also compared for inclusions and other impurities.

High Acoustic Impedance and Attenuation Backing for High-Frequency Focused P(VDF-TrFE)-Based Transducers.

Backing materials with tailored acoustic properties are beneficial for miniaturized ultrasonic transducer design. Whereas piezoelectric P(VDF-TrFE) films are common elements in high-frequency (>20 MHz) transducer design, their low coupling coefficient limits their sensitivity. Defining a suitable sensitivity-bandwidth trade-off for miniaturized high-frequency applications requires backings with impedances of >25 MRayl and strongly attenuating to account for miniaturized requirements. The motivation of this work is related to several medical applications such as small animal, skin or eye imaging. Simulations showed that increasing the acoustic impedance of the backing from 4.5 to 25 MRayl increases transducer sensitivity by 5 dB but decreases the bandwidth, which nevertheless remains high enough for the targeted applications. In this paper, porous sintered bronze material with spherically shaped grains, size-adapted for 25-30 MHz frequency, was impregnated with tin or epoxy resin to create multiphasic metallic backings. Microstructural characterizations of these new multiphasic composites showed that impregnation was incomplete and that a third air phase was present. The selected composites, sintered bronze-tin-air and sintered bronze-epoxy-air, at 5-35 MHz characterization, produced attenuation coefficients of 1.2 and >4 dB/mm/MHz and impedances of 32.4 and 26.4 MRayl, respectively. High-impedance composites were adopted as backing (thickness = 2 mm) to fabricate focused single-element P(VDF-TrFE)-based transducers (focal distance = 14 mm). The center frequency was 27 MHz, while the bandwidth at -6 dB was 65% for the sintered-bronze-tin-air-based transducer. We evaluated imaging performance using a pulse-echo system on a tungsten wire (diameter = 25 μm) phantom. Images confirmed the viability of integrating these backings in miniaturized transducers for imaging applications.

Analysis of mechanical properties of 3D printed metallic specimens of aluminum (CL31) bronze (CL80) material manufactured at varying laser scanning speed

In our research work, we analyzed the mechanical properties of 3D-printed metallic specimens of aluminium bronze material. In our evaluation, we had five groups of specimens, manufactured at different laser scanning speeds. In total, we had 25 specimens for which we examined various parameters like ultimate tensile strength, engineering yield point, relative strain, and hardness. Results showed that specimens prepared with a lower laser scanning speed of 300mm/s showed the lowest tensile strength. The tensile strength increased with increasing laser scan speed and the highest tensile strength was attained by specimens of the fourth group that were produced at a laser scanning speed of 500mm/s. The relative strain of specimens also increased with the increasing scan speed of the laser. The Brinell hardness test also showed an elevation in hardness values with increasing laser scan speeds.

Investigation of Upgraded Technology for Plasma Spraying of Bronze Powder Using the Combined Process with Hydrocarbon Additions

The object of the research is thermal spray process for the formation of metal coating from bronze powder in plasma-fuel variant, using direct current (DC) electric arc plasma torch, on steel samples. The aim of the work was to investigate and develop the technology for plasma-fuel spraying of functional coatings (for wear-resistant and antimicrobial applications) on machine-building and medical purpose pieces with increased process capacity and moderate energy consumptions in a comparison with conventional thermal spray technologies with use of inert and oxygen-free gas media. During the study, using experimental and thermodynamic estimation methods, the thermal and chemical parameters of the process under the spraying conditions at ambient pressure were characterized, which made it possible to determine the area of preferred regimes of the developed technology. On the modernized testing unit for plasma spraying of metal powders with power of up to 40 kW, operating using a controlled combination of three types of gases – technical nitrogen and propane-butane (LPG) with compressed air, the measurement and optimization of the operating and constructive/assembling parameters of the system for aluminum bronze coating spraying were established. In this case, the experiments were carried out using the designed fuel intensifier, which is joined with the PP-25 arc plasma torch, as well as additional technological equipment (protective shroud). For samples of the resulting coatings with a thickness of 100 to 450 mm from the bronze material, testing of phase composition and some parameters of the resulting coatings on steel products was carried out. Operating capacity of the proposed process reaches 7–15 kg/h for bronze powder when using a moderate power of the torch – up to 35–40 kW and a limited flow rate of hydrocarbon gas (for example, LPG of the SPBT grade) – 0.1–0.35 kg/h. Analysis of the energy efficiency parameters of the developed technology, as well as its calculated technical characteristics, in a comparison with plasma and combined equipment of a similar purpose, showed that it has an advantage in terms of target indicators, in particular, in terms of energy consumption and total energy efficiency of the spraying unit, not less than 20–30 %. This makes it to proceed later to the stage of application of this technology into production based on a new process for the metal coating formation, in particular with antimicrobial properties, with improved energy efficiency of the process.

Brazing of Different Metal Alloys with Highly-Silver Flux Addition and Microstructure Investigation

In this study, it was investigated that two different metal alloys can be soldered with the help of industrial flux. Thus, the soldered state of two different metals used in areas such as defense, automotive, and battery was examined. A low-carbon steel alloy and a GBZ20 grade bronze material were used for brazing. An industrial flux was used as an intermediate material. Flux contains high levels of silver (Ag), as well as Cu, Zn, Pb, and Ni elements. A design is prepared between the two materials during soldering. With the flame heating method, the sample temperature was increased to approximately 800°C. After the experiment, rapid cooling was done in water. Inspection of the solder intermediate zone was examined with the help of a scanning electron microscope (SEM). Chemical analyzes of the materials were followed. Thus, two different metals are combined with a flux-assisted soldering process.

One-step ball-milling synthesis of cesium tungsten bronze nanoparticles and near-infrared shielding performance

Tungsten bronze (MxWO3) materials have been widely used as thermal insulation for architectural glass because of their higher near-infrared (NIR) light shielding capacity. To solve the problems encountered in solvothermal preparation with high costs and low yields, this study has developed a facile, eco-friendly, effective, but low-cost method, with no need for any annealing process, for promoting the large-scale fabrication of cesium tungsten bronze (CsxWO3, x = 0.32) nanomaterials for potential thermal insulation windows applications. In the proposed ball-milling process, the tungstic acid material could be reduced to hydro tungsten bronze (HxWO3) by cellulose, while the cesium ions (Cs+) could be gradually incorporated into the interspace until the formation of Cs0.32WO3 (Cs/W atomic ratio = 0.32), with an average particle size of ∼33 nm after a 15 h ball-milling process. The reaction mechanism has been investigated in detail via particle structural analysis and optical performance characterization. The obtained Cs0.32WO3 nanoparticles are dispersed in a solution composed of surfactant (s) and polymer (s) which can form a thin film with a thickness of about 2 μm on a glass substrate, by a spinning coating or casting method, to exhibit high visible (Vis) light transmittance (T566nm = 72.6%), and excellent NIR-shielding capability (T1388nm = 5.3%), reflected by good heat-insulating performance in practice use. This work will pave a new path for large-scale production of Cs0.32WO3 nanomaterials with low costs and high performance, beneficial for practical applications in energy-saving glass coatings.

Visualization of bronze material structure in virtual reality

Wydawnictwo SIGMA-NOT wydaje czasopisma fachowe informujące swoich czytelników o najnowszych osiągnięciach naukowych i nowoczesnych rozwiązaniach technicznych w Polsce i na świecie, popularyzuje problemy techniczne oraz poszerza wiedzę i kulturę techniczną.

Novel High-Tin Bronze and Nb3Sn Multifilamentary Wires

We developed a method for manufacturing a high Sn concentration bronze material with high ductility. The high-Sn bronze was used to produce multifilamentary wires, and their characteristics were evaluated. To increase the Sn content of the bronze and ensure ductility, the δ-phase (Cu <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">41</sub> Sn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> ), which is a eutectoid when the Sn content is greater than the Cu-Sn solid-solution limit, was replaced with a ternary compound by the addition of Ti. The compound was further refined by hot forging to develop ductility. In this study, 1615-filament wires were produced using the high Sn concentration bronze and a commercial bronze for comparison. Each wire was heat treated with different conditions, and their superconducting properties were evaluated. The area ratio of the Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Sn phase was higher with the high-Sn bronze alloy irrespective of the heat-treatment temperature. The critical current density was improved for the high-Sn bronze for heat treatment at 625 °C or lower, but when the treatment was performed at 650 °C, the Ti concentration in the Nb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> Sn phase exceeded 2.0at% and the upper critical magnetic field deteriorated dramatically.

Effects of machining parameters on surface morphology of porous bronze during monocrystalline diamond cutting

Porous bronze materials manufactured by powder metallurgy require further machining to improve the surface quality and shape accuracy. However, conventional machining with carbide tools and PCD tools can lead to serious pore failure problems. In this paper, monocrystalline diamond (MCD) tools were used to carry out the milling experiments on porous bronze at different machining parameters. The pore area and diameter of the machined surface were used statistically to analyze the effect of different machining parameters on the pore structure during the cutting process. For the porous bronze exhibiting different removal patterns from other materials during the experiments, a novel porous cutting model based on random powder particles was created to verify that the pore structure significantly altered the cutting mechanism of the bronze material at different cutting depths. The experimental results showed that the cutting speed also had a great influence on the porosity, due to the positive strain rate effect of the bronze material, while the influence of feed rate was relatively small. During the cutting process, the material was extruded and rubbed by the cutting edge arc and tool flank face, causing the material to flow into the nearby pores, leading to a decrease in surface porosity. The conformed porosity of the machined surface demonstrates that CNC machines with MCD tools can meet the machining requirements of porous bronze and solve the pore blockage problem in porous materials. This provides a technical reference for the choice of processing methods for porous plastic materials.

Structure of tetragonal tungsten bronze materials by X-ray diffraction and electron techniques

Structure of tetragonal tungsten bronze materials by X-ray diffraction and electron techniques

Investigation of Microstructural, Mechanical and Corrosion Properties of Cu-10Sn Bronze Parts Produced by Selective Laser Melting

In this study, the production of full-density Cu-10Sn bronze parts by selective laser melting (SLM) technique and the examination of microstructural, mechanical and corrosion properties were carried out. Cu-10Sn pre-alloyed powders produced by gas atomization technique were shaped using SLM technique within selected parameters and then microstructural properties were determined. Depending on the microstructural properties, the mechanical and corrosion behaviors were determined. The obtained results were compared with similar bronze materials produced by conventional methods. Different characterization techniques were used for microstructural characterization. The microstructure of the Cu-10Sn alloy was observed to consist of dendritic primary α and δ-Cu41Sn11 phases. According to the mechanical test results of the samples produced at densities of 8.75 g cm-3 at room temperature, the yield strength was measured as 420 MPa, the tensile strength was 578 MPa, the elongation was 32 % and the hardness value was 160.3 HV0.2. For the electrochemical experiments, the corrosion rate of the samples was found to be 4.38 mpy. As a result of the productions and experiments, it was determined that the samples produced by the SLM method provide very good mechanical and corrosion properties compared to the literature.

Design and Analysis of Marine Propeller

This paper presents a comparison between propellers varying in design to evaluate their performance and efficiency. A propeller is a type of fan that transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of airfoil shape blade and fluid is accelerated behind the blades which generates two forces, one along the longitudinal direction of ship which is the axial force called thrust force and tangential force which produce the required torque. As propeller has great influence on the propulsive performance of ship, propeller design is important technology for energy saving in ship propulsion. Generally, alloy of aluminium or bronze material are used for manufacturing of marine propeller. The propeller is a complex geometry which requires high end modelling software. The solid model of propeller is developed in HydroComp PropCad 2005 and SolidWorks 2019 and a tetrahedral mesh is generated for this model using HYPER MESH and simulation is carried out using SolidWorks. By considering all the study and benefits this model helps to find the optimum propeller for defined objectives. Based on optimized parameters the propellers performance is calculated by the simulation of designed model.

Obtaining and Analysis of a New Aluminium Bronze Material Using Induction Furnace

Obtaining and Analysis of a New Aluminium Bronze Material Using Induction Furnace