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In the current study, outdated Ampicillin drug (AMP) was assessed as a potent and environmentally friendly corrosion inhibitor for 60Cu-40Zn brass by gravimetric analysis, in nitric acid solution in a concentration range of 0.5M-2M. The findings revealed that AMP exhibited high corrosion inhibition performance, and its efficiency increased with the increase of its concentration and the concentration of nitric acid. In addition, potentiodynamic polarization (PDP) curves, electrochemical impedance spectroscopy (EIS), and surface analysis were conducted in 0.5 M HNO3 solution. Ampicillin was found to act as a mixed-type inhibitor, and its inhibitory efficiency increased with the addition of AMP up to 92% at its optimal concentration of 10 mM. However, it decreased slightly with increasing temperature. The adsorption thermodynamic parameters demonstrated that the medicine adsorbed onto a brass surface in accordance with the Langmuir isotherm, via physisorption and chemisorption mechanism. Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX) and FT-IR/ATR analysis clearly evidenced the strong adsorption of AMP onto the brass surface, leading to higher corrosion resistance of the brass alloy in the inhibitive solution. Theoretical parameters of drug molecules were computed, using density functional theory (DFT) and Fukui indices, to better understand the adsorption mechanism of AMP molecules onto the brass surface. A close agreement between quantum calculations and experimental results was observed. [ABSTRACT FROM AUTHOR]

WEDM is efficient in machining complicated profiles with high dimensional accuracy. The Nickel-aluminum-bronze (NAB) is a high-strength alloy with exceptional corrosion-resistant properties and is abundantly used in marine applications such as propellers, valves, and seawater pumps. The previous literature reports numerous instances of WEDM-induced simple profiles on NAB alloy employing brass and molybdenum wires; however, the WEDM of detailed profiles on NAB alloy using brass wire encapsulated with zinc layer is scarce to find. Hence, in the present article, we proposed an experimental framework to create complex profiles on NAB alloy using the zinc-enveloped brass wire in the WEDM process. The control variables, namely the pulse on time, servo voltage, current, and pulse off time, were varied to report their influence on the experimentally determined machining time (MT), kerf width (KW), and corner error (CE). The statistical analysis revealed that pulse on time affects the KW and CE dominantly, whereas the current has high relative significance when MT is concerned. FESEM images showed that WEDM processing at high discharge energy settings generated many large-sized voids, large melted deposits, deep craters, and microcracks on the surface. Conversely, WEDM processing at low discharge energy settings caused small-sized voids, small melted deposits, and shallow craters. Microcracks are not visible on the surface after WEDM processing at a low discharge energy level. Energy dispersive x-ray (EDX) analysis discerned the substantial deposition of zinc on the machined surface from the zinc-coated brass wire ensuing the machining operation. [ABSTRACT FROM AUTHOR]

This document is a list of references to various research articles on corrosion control and inhibition in different environments. The articles cover a range of topics, including the use of different compounds and materials as corrosion inhibitors for metals such as mild steel, copper, and brass. The studies involve both theoretical and experimental investigations, and some articles also discuss the synthesis and characterization of the inhibitors. The articles provide valuable insights into the development of effective corrosion prevention strategies for different applications. [Extracted from the article]

By taking advantage of typical dealloying and subsequent aging methods, a novel homogeneous porous brass with a micro/nano hierarchical structure was prepared without any chemical modification. The treatment of commercial brass with hot concentrated HCl solution caused preferential etching of Zn from Cu62Zn38 alloy foil, leaving a microporous skeleton with an average tortuous channel size of 1.6 μm for liquid transfer. After storage in the atmosphere for 7 days, the wettability of the dealloyed brass changed from superhydrophilic to superhydrophobic with a contact angle > 156° and sliding angle < 7°. The aging treatment enhanced the hydrophobicity of the brass by the formation of Cu2O on the surface. By virtue of the opposite wettability to water and oil, the aged brass separated surfactant-stabilized water-in-oil emulsions with separation efficiency of over 99.4% and permeate flux of about 851 L·m−2·h−1 even after recycling for 60 times. After 10 times of tape peeling or sandpaper abrasion, the aged brass maintained its superhydrophobicity, indicating its excellent mechanical stability. Moreover, the aged brass still retained its superhydrophobicity after exposure to high temperatures or corrosive solutions, displaying high resistance to extreme environments. The reason may be that the bicontinuous porous structure throughout the whole foil endows stable mechanical properties to tolerate extreme environments. This method should have a promising future in expanding the applications of alloys. [ABSTRACT FROM AUTHOR]

The reactivities of various fatty monoacids and diacids on copper metal-containing surfaces were investigated through reflection–absorption infrared spectroscopy. The formation of copper carboxylates is detected on pure copper surfaces, while copper and zinc carboxylates are simultaneously formed on brass surfaces. Following the decrease of acid carbonyl and the formation of carboxylate infrared bands, it is shown that fatty monoacids C8 and C10 react with clean/polished copper and its zinc alloy within 2–4 h, while those with chains > C12 react within days. At the end of the processes, only the corresponding metal carboxylates are detected in all cases. An explanation for the above is offered on a molecular mobility and acidity basis, where the lower monoacids (liquids in room temperature), also having lower pKa values, favor higher reaction rates. Furthermore, it is argued that longer-chain fatty monoacids, when deposited from their solutions, allow for favorable orientation resulting in self-assembled monolayer-type molecular packing on the copper surface, which may additionally rationalize the slower reaction. Interestingly, fatty diacids do not form any carboxylate products under the same conditions, as it is argued that their molecules may efficiently pack as self-assembled multilayers on copper and ultimately protect it. The possible implications of the fatty monoacid and diacid behavior on the archaeological organic residues level and regarding the stability of copper alloys are discussed. [ABSTRACT FROM AUTHOR]

• Non-degraded centuries-old brass objects are rare. • Brass sequins appear pristinely preserved in a series of 16th-century altarpieces. • Key information on the factors affecting the reactivity of brass has been obtained. • The manufacturing process has a central role on the stability of these objects. Brass is a relatively stable alloy but it tends to tarnish over time due to the interaction with the atmosphere. Thus, it is rare to observe centuries-old brass objects untouched by the passing of time. For this reason, the pristine appearance of hundreds of brass sequins in the Enclosed Gardens of Mechelen (reliquary altarpieces produced between 1530 and 1550) is remarkable. In this study, the chemical and metallographic characterization of such unexpectedly well-preserved objects is presented. The results revealed the reason for their stability to be a combination of high-quality materials (i.e. medium Zn content, low impurities) and optimal surface properties (i.e. high homogeneity, low roughness), indicating the high level of expertise of the craftsmen who produced them. Novel fundamental insights on the historical manufacturing method of metallic sequins were also obtained. [ABSTRACT FROM AUTHOR]

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This article deals with a comparative study of the thermomechanical behavior of coppersteel and brass-steel tribological couples, as a function of functional parameters: contact mode, dynamic torsor, contact kinematics and the materials making up the tribosystem. For this purpose, friction and wear tests were carried out using a pin-disc tribometer, in an atmospheric environment. This consists of a copper or brass pin rubbing dry against a rotating steel disc. A Comsol Multiphysics numerical code was used to evaluate contact temperature, mechanical stresses and deformations at the interface of the pairs. The results obtained show that the abovementioned parameters have a significant influence on the tribomechanical and thermal behavior of the two couples. Indeed, the dissipation of heat by sliding modifies the physicochemical and mechanical properties of the materials, and promotes the oxidation process. In addition to the formation of oxides, the mutual material transfer mechanism plays a key role in the friction and wear of the couples. The discussion of the results is based on macroscopic and microscopic observations of worn surfaces and the interfacial phenomena resulting from sliding. [ABSTRACT FROM AUTHOR]

Purpose: To compare the superficial dose when using brass mesh bolus (BMB), no bolus, or 3 mm tissue‐equivalent bolus with a pseudo‐flash volumetric modulated arc therapy (VMAT) breast treatment planning technique. Methods: Two different beam arrangements for right‐sided irradiation and one beam arrangement for bilateral irradiation were planned on an inhomogeneous thorax phantom in accordance with our clinical practice for VMAT postmastectomy radiotherapy (PMRT). Plans were optimized using pseudo‐flash and representative critical organ optimization structures were used to shape the dose. Plans were delivered without bolus, with 3 mm tissue‐equivalent bolus (TEB), or with one‐layer BMB. Optically stimulated luminescence dosimeter (OSLD) and radiochromic film measurements were taken and analyzed to determine the superficial dose in each case and the relative enhancement from the no bolus delivery. Results: Superficial dose measured with OSLDs was found to be 76.4 ± 4.5%, 103.0 ± 6.1%, and 98.1 ± 5.8% of prescription for no physical bolus (NB), TEB, and BMB, respectively. Superficial dose was observed to increase from lateral to medial points when measured with film. However, the relative increase in superficial dose from NB was consistent across the profile with an increase of 43 ± 2.1% and 34 ± 3.3% of prescription for TEB and BMB, respectively. The results are in good agreement with expectations from the literature and the experience with tangential radiotherapy. Conclusion: Three millimeter TEB and one‐layer BMB were shown to provide similar enhancement to the superficial dose compared to delivery without bolus. BMB, which does not significantly affect dose at depth and is more conformal to the patient surface, is an acceptable alternative to 3 mm TEB for chest wall PMRT patients treated with pseudo‐flash PMRT. [ABSTRACT FROM AUTHOR]

John Miller's book, "The Modern Brass Ensemble in Twentieth-Century Britain," explores the history and development of brass ensembles in Britain. The book highlights the significant role played by the Distin Family Brass Quintet in promoting Adophe Sax's newly designed valve instruments in the 19th century. It also discusses the emergence of amateur brass bands in Britain, which were initially called "saxhorn" bands. The book traces the evolution of brass ensemble music throughout the 20th century, with a focus on the British context. Miller argues that British professional brass playing, combined with the amateur brass band movement, created a unique and influential brass ensemble culture in Britain. The book also examines the impact of key figures such as Philip Jones and the Philip Jones Brass Ensemble on the development of brass ensemble music. Overall, Miller's book provides a comprehensive and detailed account of the history and significance of brass ensembles in Britain. [Extracted from the article]

Leaded (Pb) brass components used in water pipeworks are prone to lead leaching following soldering or brazing during installation. Synchrotron radiation X-ray imaging shows that in the initial state of potable-water grade brass samples, Pb exists mainly as isolated or linked-together particles from sub-micron to several microns large. On heating to the usual soldering temperature of ~200 °C, the Pb contents surface rapidly via diffusion pathways involving an interpenetrating Pb–brass structure with orientation relationship (11 1 ̅ )α-brass//(220)Pb; [011]α-brass//[ 1 ̅ 13]Pb. On heating to the usual brazing temperature of 700 °C, the Pb particles melt and expand in volume, with the Pb content forced into the brass lattice preferentially along {101}α-brass planes, forming Pb phase of low sphericity or even large sheets. On immersion in water, the surfaced Pb particles are oxidized to form PbO needles along the normal direction of { 2 ̅ 2 ̅ 2 }PbO planes, which are then easily washed away to cause Pb leaching. [ABSTRACT FROM AUTHOR]

A significant increase in roughness of dieless-drawn wires due to the strain-induced roughness phenomenon has been documented. For small-diameter wires, even a slight surface relief creates stress concentrations that may contribute to the wire breakage during cold drawing. This, in turn, significantly limits the achievable diameter of the product and the efficiency of drawing process. The present study, however, demonstrates that reducing the wire roughness is possible by combining the dieless and conventional drawing methods. Thus, it is possible to improve the process workability threefold when compared to dieless drawing alone, and the product quality is simultaneously improved. In addition, the surface defects typical to the dieless-drawn wires have been significantly reduced, resulting in an increase in the wire strength. This new combined technology enables a significant reduction in the wire diameter and facilitates an economical large-scale production of ultra-thin wires. In addition, based on the classic drawing and dieless drawing process, a brass wire with a diameter of 0.017 mm has been manufactured. Six times thinner than a human hair, it is believed to be the thinnest long brass wire currently manufactured in the world. [ABSTRACT FROM AUTHOR]

Herein, microchip laser-based laser-ablation spark-induced breakdown spectroscopy (LA-SIBS) was developed to realize the quantitative elemental analysis of minor elements in bismuth brass with minimal destruction. A simple spark discharge unit and compact multichannel fiber spectrometer in non-gated operation mode were employed. The characteristics of spark discharge were analyzed, and the effects of discharge voltage and capacitance of the energy storage capacitor on the signal intensities were studied. With the assistance of spark discharge, the plasma temperature increased significantly. The detection limits of bismuth and tin were determined to be 21.6 ± 1.1 and 100 ± 5 ppm, respectively, demonstrating a 10–22-fold enhancement in the detection limit obtained by microchip laser-based LIBS. It was shown that spark discharge could improve the analytical sensitivity of the portable LA-SIBS system. This work can help construct a portable and miniaturized system to realize more rapid, sensitive, and high spatial resolution online elemental analysis than LIBS systems consisting of the same microchip laser and fiber spectrometer. [ABSTRACT FROM AUTHOR]

An anodic oxidation process for red copper and brass was introduced. The bath composition and process conditions are as follows: sodium hydroxide 150-200 g/L, ammonium molybdate 0.1-0.3 g/L, temperature 80-90 °C, current density 0.6-1.5 A/dm², air agitation or mechanical stirring, and time 20-30 min. The anodic oxide film obtained is black with a thickness of 4-5 µm, and adhered tightly to the substrate. It is better to conduct sealing treatment after anodic oxidation to improve the corrosion resistance of anodic oxide film. [ABSTRACT FROM AUTHOR]

As for the application environment of silver-coated copper on the tulip contacts of disconnecting switch, silver coatings with different thicknesses were electroplated on brass. The corrosion resistance and wear resistance of brass and silver coatings were studied by atmospheric corrosion test, electrochemical corrosion test, and friction and wear test. The results showed that the corrosion resistance and wear resistance of brass could be improved by silver electroplating. The 10 µm-thick silver coating featured the best corrosion and wear resistance. [ABSTRACT FROM AUTHOR]

Despite the benefits of learning an instrument, many students drop out early because it can be frustrating for the student, expensive for the caregiver, and loud for the household. Virtual Reality (VR) and Extended Reality (XR) offer the potential to address these challenges by simulating multiple instruments in an engaging and motivating environment through headphones. To assess the potential for commercial VR to augment musical experiences, we used standard VR implementation processes to design four virtual trumpet interfaces: camera-tracking with tracked register selection (two ways), camera-tracking with voice activation, and a controller plus a force-feedback haptic glove. To evaluate these implementations, we created a virtual music classroom that produces audio, notes, and finger pattern guides loaded from a selected Musical Instrument Digital Interface (MIDI) file. We analytically compared these implementations against physical trumpets (both acoustic and MIDI), considering features of ease of use, familiarity, playability, noise, and versatility. The physical trumpets produced the most reliable and familiar experience, and some XR benefits were considered. The camera-based methods were easy to use but lacked tactile feedback. The haptic glove provided improved tracking accuracy and haptic feedback over camera-based methods. Each method was also considered as a proof-of-concept for other instruments, real or imaginary. [ABSTRACT FROM AUTHOR]

The critical applications of difficult-to-machine Inconel 617 (IN617) compel the process to be accurate enough that the requirement of tight tolerances can be met. Electric discharge machining (EDM) is commonly engaged in its machining. However, the intrinsic issue of over/undercut in EDM complicates the achievement of accurately machined profiles. Therefore, the proficiency of deep cryogenically treated (DCT) copper (Cu) and brass electrodes under modified dielectrics has been thoroughly investigated to address the issue. A complete factorial design was implemented to machine a 300 μm deep impression on IN617. The machining ability of DCT electrodes averagely gave better dimensional accuracy as compared to non-DCT electrodes by 13.5% in various modified dielectric mediums. The performance of DCT brass is 29.7% better overall compared to the average value of overcut (OC) given by DCT electrodes. Among the non-treated (NT) electrodes, the performance of Cu stands out when employing a Kerosene-Span-20 modified dielectric. In comparison to Kerosene-Tween-80, the value of OC is 33.3% less if Kerosene-Span-20 is used as a dielectric against the aforementioned NT electrode. Finally, OC's nonlinear and complex phenomena are effectively modeled by an artificial neural network (ANN) with good prediction accuracy, thereby eliminating the need for experiments. [ABSTRACT FROM AUTHOR]

A description of the process of metal evaporation from liquid alloys at an atmospheric pressure has a practical value for both the smelting and remelting of their scraps. The quantities of volatile components that are eliminated in these processes depend on many factors of which the type of melting device, the method and conditions of the process performance, the alloy composition and the kind of applied atmosphere are of the greatest importance. In this paper, the results of the research on zinc evaporation from brass scraps containing 10.53 wt% Zn are presented. The experiments were conducted using the thermogravimetric method at 1080 ÷ 1240 °C in a helium atmosphere. In the research, the levels of zinc removal from copper ranged between 82% and 99%. The values of the overall mass transfer coefficient for zinc kZn, determined based on the experimental data, ranged from 4.74 to 8.46 × 10−5 ms−1. The kinetic analysis showed that the rate of the analysed process was determined by mass transfer in the gas phase. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office 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.)

Late precontact- and contact-period sites often produce multiple sources of chronological information, including stratigraphy, radiocarbon dates, European trade goods, and pottery seriation patterns. In this article, we describe a step-by-step approach to incorporating such information in an OxCal-based Bayesian chronology model, with special emphasis on incorporating trade-good dating into radiocarbon-based modeling. The Middle Grant Creek site in Illinois is an American Indian site that has yielded a number of European copper and brass trade goods along with extensive ceramic, faunal, floral, and lithic artifacts. Our modeling addresses issues resulting from an inversion in the radiocarbon calibration curve during the late precontact period and produces surprisingly different results depending on the boundary conditions applied to the model. We consider the probabilities produced by the models, propose the most likely chronology for Middle Grant Creek, and provide detailed OxCal scripts and examples that other researchers may adapt to their circumstances and preferences. We also describe lessons learned related to chronological modeling of sites where the radiocarbon curve contains significant inversions. [ABSTRACT FROM AUTHOR]

The 17th-century manuscript M7709 (held in the Matenadaran, Yerevan, Armenia) includes an Armenian copy of the History of the City of Brass , to which an unknown scribe has added short poems about Alexander the Great. The final article of three that together present the Alexander poems of M7709 in full, with English translation, for the first time, this article focuses on the last fourteen: the deaths of Darius III and Alexander, and concluding poems. It adds commentary on the poems' relationship to the corresponding part of the History of the City of Brass on each page, proposing textual reasons why the scribe added the poems where he did. Across the three articles, this commentary delves into textual relationships beyond the pages of M7709, linking the Armenian History of the City of Brass , Alexander Romance and other texts and traditions, to show how this manuscript is situated amid wider networks of circulating literature. As a microhistorical study, it seeks to provide illumination into the macrohistory of medieval and early modern literature in and beyond the Caucasus. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to develop a novel Bonwill⁃Hawley method (Bonwill⁃Hawley arch form based on CBCT image) for the assessment of dental crowding, and to investigate and compare the accuracy and eligibility with the conventional brass wire and caliper methods under different crowding conditions. Material and methods: Sixty patients with the pair of plaster casts and CBCT data were collected. All the casts were marked and transformed into digital models using iTero scanner, and imported into OrthoCAD software to measure the required space. Using the conventional brass wire (M1) and caliper methods (M2), the available space and dental crowding were measured and calculated basing on digital models, respectively. Correspondingly, the axial planes in the level of dental arches were oriented and captured from the CBCT images to draw the Bonwill⁃Hawley arch forms (M3), which were used to measure and calculate the available space and dental crowding. For each method, intra and inter-examiner reliabilities were evaluated with intra-class correlation coefficients (ICCs). Wilcoxon test and Kruskal–Wallis test were performed for statistically analyzing the discrepancy among different groups. Results: Both intra- and inter-examiner reliability were generally excellent for all parameters obtained by the three methods, except for the dental crowding measured using M1(ICC: 0.473/0.261). The dental crowding measured using M2 were significantly increased in mild, moderate and severe-crowding groups compared with M1. However, no significant difference was detected between M1 and M3 in severe-crowding group (maxilla, p = 0.108 > 0.05; mandible, p = 0.074 > 0.05). With the deterioration of crowding condition, the discrepancy of dental crowding between M1 and M2, or M1 and M3 were significantly decreased (maxilla, M2-M1, mild VS serve, p = 0.003 < 0.05; maxilla, M3-M1, mild VS serve, p = 0.003 < 0.05; mandible, M2-M1, mild VS serve, p = 0.000 < 0.001; mandible, M3-M1, mild VS serve, p = 0.043 < 0.05). Conclusion: Dental crowding measured using the novel Bonwill⁃Hawley method was relatively greater than the caliper method, but not exceeding the brass wire method, which wound gradually come close to the brass wire method with the deterioration of crowding condition. Clinical relevance: The Bonwill⁃Hawley method basing on CBCT image proved to be a reliable and acceptable choice for orthodontists to analyze the dental crowding. [ABSTRACT FROM AUTHOR]

The problem of the convergence of the iterates of operators or of a sequence of operators is discussed in a general framework related to the fixed point theory, but with a permanent look towards the theory of linear approximation operators. The results are obtained for operators not necessarily linear. Some examples including the class of approximation operators defined by H. Brass are given. [ABSTRACT FROM AUTHOR]

In this paper the influence of various modes of preliminary heat treatment of workpieces made of M1 copper alloy and L63 brass on the possibility of forming a favorable fine-grained structure for further processing using severe plastic deformation during radial-shear rolling was investigated. The results of the microstructure study obtained during the physical experiment had proved once again that for copper the most rational pre-heat treatment is quenching at a temperature of 500°C, since it allowed the initial structure to be refined from 80 microns to 50 microns, while the structure of copper after quenching consists of polyhedral grains elongated in the direction of the cooling gradient. For brass L63, annealing is the most suitable pre-heat treatment, since with slow cooling in this alloy, the most complete transition of the ß-phase to the a-phase is ensured, which favorably affects the further processing of this alloy using radial-shear rolling. [ABSTRACT FROM AUTHOR]

A comparative analysis of brasses alloys, namely lead-free CuZn (CB771) and lead containing CuZn (CB770), was conducted in this article. The results of the comparative analysis and experimental investigations aimed to provide comprehensive knowledge about the thermophysical properties and solidification characteristics of these alloys. Thermodynamic simulations using Thermo-Calc software and modifications in the chemical composition of the CB771 alloy were employed to approximate its characteristics to those of the lead containing CuZn alloy. Thermal-derivative analysis of the alloys and a technological trial were carried out to determine their solidification characteristics, fluidity, and reproducibility. The casting trials were conducted under identical conditions, and the results were compared for a comprehensive analysis. Additionally, a solidification process simulation was performed using MagmaSoft software to match the thermophysical properties. The aim of this research was to achieve maximum consistency between the simulation results and experimental investigations. [ABSTRACT FROM AUTHOR]

With this text I am publishing three identical brass spikes with production stamps, from the hull of the Saint Nicholas Bay Shipwreck (SNBS). While identical, the stamps were illegible to the naked eye. By deciphering one of them, we were able to establish that they relay the name of the largest Austro-Hungarian private shipyard of the 'Long nineteenth century,' the Technical Establishment of Trieste (Stabilimento Tecnico Triestino, 1857-1929). The production stamps provided the latest terminus post quem for the formation of the archaeological site in Saint Nicholas Bay and a tangible link between the historic ship, as presented in the archaeological record, and the Austro-Hungarian coast of the Adriatic Sea. This paper summarises the archaeology of the SNBS, discusses the fastening system of its wooden hull, analyses the three artefacts and assesses their significance for the interpretation of the underwater archaeological site. [ABSTRACT FROM AUTHOR]

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The paper offers relevant information concerning Klášťov, the dominant summit of the Vizovice Hills in eastern Moravia, where Moravia’s highest-positioned stronghold was built in the period of the Lusatian Urnfield culture. Later, in the 9th and 10th c., it was used by the domestic population above all for cult purposes; traces of a more permanent occupation have not been detected there yet. Text also presents an exceptional local find of a brass inlaid trefoil iron sword set fitting, probably a local imitation of Carolingian models (?). It represents a high-quality, professionally made art and craft product whose popularity culminated in the second and third quarters of the 9th c. in the West; it might have occurred also later in the Moravian milieu. [ABSTRACT FROM AUTHOR]

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Welding and joining of brass CuZn30-aluminum AA1100 were obtained using micro two-stage refilled friction stir spot welding (mTS-RFSSW), which was carried out to eliminate the holes formed by the micro friction stir spot welding (mFSSW) process. The mTS-RFSSW process begins with the mFSSW welding process using tools with a pin inner diameter of 2.69 mm, pin outer diameter 1.811 mm and shoulder diameter of 4.954 mm, followed by a second stage process called mTS-RFSSW, which is a hole closing process using a tool with a pinless tool with shoulder diameter 4.954 mm. This study aimed to determine the effect of the second stage of dwell time on the mechanical properties produced in the mTS-RFSSW welding technique using brass CuZn30 and aluminum AA1100 with a thickness of 0.42 mm. In this study, the variable parameter is the second stage dwell time which varies from 3 s, 4 s, 5 s, and 6 s, respectively. An optical microscope that aims to observe the macrostructure shows that an upward hook is formed in each joining process. Based on the scanning electron micrograph, the resulting formation of different intermetallic com- pounds (IMC) with varying thicknesses occurs in every variation of dwell time. The high dwell time indicates discontinued IMC, which affects the ten- sile force. The IMC formed at the interface of brass CuZn30 and aluminum AA1100 is dominated by more than 30 % Cu. The highest hardness value is found in the stir zone because the formation of intermetallic compounds influences refined grains. The highest maximum shear force and cross tensile force was obtained 371.35 N and 54.88 N, respec- tively, in the dwell time of 3 s. The result of fracture properties after the lap shear test shows the pres- ence of small dimples with microcracks that indi- cate brittle failure. [ABSTRACT FROM AUTHOR]

Several formulations of artificial saliva have been used for corrosion studies. The present work focuses on the effect of different saliva formulations on the composition of the surface film formed on CuZn37 brass alloy by X‐ray photoelectron spectroscopy (XPS), in order to clarify the corrosion mechanism of historical brass wind instruments when used. Three different saliva solutions, Darvell (D), Carter‐Brugirard (C‐B) and SALMO, were selected. They differ for the content of the organic compounds. The XPS results show the presence of a film made of CuSCN and zinc‐phosphate on the brass exposed to C‐B and SALMO. In the case of samples exposed to D formulation, phosphorus is not revealed, a decrease in the zinc content in the film is detected and the S 2p shows the presence of a second component together with the one ascribed to CuSCN. A comparison with the results obtained on the pure metals in the presence of the organic compounds suggests that the formation of zinc and copper complexes may lead to thin and less protective surface film and thus to the observed high corrosion rates. [ABSTRACT FROM AUTHOR]

Copyright of Yildiz Journal of Art & Design is the property of KARE Publishing 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.)

In order to automatically process ultra-fine copper tube electrodes, this study proposes a new method of ultrasonic vibration processing of ultra-fine copper tube, analyzes its processing principle, designs a new set of experimental processing equipment and completes the processing of 1.206 mm inner diameter, 1.276 mm outer diameter with core brass tube. Not only can the copper tube be completed with core decoring, the surface of the processed brass tube electrode also has good integrity. The effect of each machining parameter on the surface roughness of the electrode after machining was investigated by a single-factor experiment and the optimal machining effect was achieved under the conditions of machining gap 0.1 mm, ultrasonic amplitude 0.186 mm, table feed speed 6 mm/min, tube rotation speed 1000 r/min and reciprocating machining two times. The surface roughness was reduced from 1.21 μm before machining to 0.11 μm, and the residual pits, scratches and oxide layer on the surface were completely removed, which greatly improved the surface quality of the brass tube electrode and prolonged its service life. [ABSTRACT FROM AUTHOR]

Brass materials are categorized in the copper alloys sub-groups with prevailing Zinc element. These materials are utilized from drinking water systems to automotive in a wide range of industrial applications due to superior properties such as strength, formability and corrosion resistance. This study aims to characterize and analyze smart and popular conducted manufacturing processes influences on the mechanical and microstructural properties of eco-friendly brass alloy. In this regard, microstructural, hardness, tensile and impact charpy tests have been carried out on extruded, extruded+annealing, forged and forged+annealing eco-brass CuZn40Pb2, CuZn38AS, CuZn21Si3P specimens. The experimental results have demonstrated that the manufacturing process type extremely influences the materials mechanical and microstructural properties. [ABSTRACT FROM AUTHOR]

In this work, we fabricated lap joints between embossed projection phosphorus bronze and flat brass through resistance projection welding (RPW). The experimental results indicated that the bronze projection moves into the softer brass without being deformed during the welding process. The tensile shear loads of the joint reached a maximum value of 273.6 N at a welding current of 5.5 kA. Under this circumstance, a reaction layer, including a columnar crystal solidification layer and a diffusion layer, is formed at the interface beside the boundary of bronze. The EDS line scan shows an elemental transition diffusion layer of about 1.5 μm between the H62 brass columnar crystal and XYK-6 phosphorus bronze. The fracture occurred on the XYK-6 side, passing through the bump instead of the welding interface, resulting in intactness of the welding interface. The results revealed that resistance projection welding is an effective method for welding copper alloys, suggesting the bright prospects of this technology in welding electrical parts. [ABSTRACT FROM AUTHOR]

Prior studies on cryogenic thermal contact resistance (TCR) measurement mainly focus on liquid nitrogen temperature region and above. There are limited solid TCR data in the lower temperature region. The present measurement is based on an RDK-408D2 two-stage G-M cryogenic refrigerator. By using the laminated method, the TCR data of brass samples in the temperature range of 10—30 K at different roughnesses and preloads are measured and the influence of different factors on TCR is discussed. The results show that the TCR of the brass contact surface in this temperature zone is between 6.89×10-4 and 1.86×10-2 m2·W/K. With a smaller roughness of the contact surface, higher temperature, and greater pre-tightening force, the TCR becomes smaller. This behavior is consistent with the conventional qualitative understanding. The above cryogenic experimental data can provide certain support for the calculation of TCR for related cryogenic application design.