Brass Plating Research Articles

ЛАТУНИРОВАНИЕ СТАЛЬНОЙ ПРОВОЛОКИ ИЗ ЭТИЛЕНДИАМИНОВЫХ ЭЛЕКТРОЛИТОВ

The compositions of the main components of copper, zinc and brass ethylenediamine electrolytes were studied for the electrochemical characteristics of the electrolysis process and the properties of the resulting coatings. The optimal composition of ethylenediamine electrolyte for brass plating has been proposed.

Recent Advances on Drawing Technology of Ultra-Fine Steel Tire Cord and Steel Saw Wire

Steel tire cord and steel saw wire represent typical precision pearlitic steel wire rods of wire products; it is a very important solar energy material with a diameter about 50 μm. This paper mainly discusses the research progress of the wire rod drawing process, and its main contents are as follows: First section—the control of the wire rod surface quality is summarized, including the thickness of the surface decarburization layer, the phase composition and thickness of the surface iron oxide scale, and the removal of surface iron oxide scale. Then, the research progress of the wire rod water bath treatment process during sorbitization is summarized. In addition, the development of brass plating technology for steel wire is summarized, including copper plating technology, coating phase composition, etc. Furthermore, the development of steel wire drawing methods is summarized. Finally, the development of the dies used in steel wire drawings is summarized.

Replacement of Copper Cyanide by Copper Sulfate on Electroless Brass Plating Process

Environmentally friendly processes and health protection are industrial requirements nowadays. Surface finishing industry demands the improvement of the composition of bath solutions, and specifically, reduction or elimination of the use of toxic substances to simplify complexity on wastewater treatment. This work presents results on the replacement of copper cyanide by copper sulfate in the composition of an electroless brass plating bath used on zamak alloy coating. The effect of the concentration of copper sulfate on the morphological and brass film color characteristics was studied. Characterization of plated pieces was made by scanning electron microscopy, optical microscopy, L*, a*, b* color parameters and by spectrophotometry and electrochemical techniques. Results indicate that copper cyanide can be successfully substituted, being possible to control the color of brass plating on this new process.

Improving the performance of cylinder liners by creating thin-layer coatings in the interface

The paper presents the technological process of brass plating of the cylinder bore. Application of the coating allows to increase the operational reliability of parts of the cylinder-piston group and the technical life of the entire engine

Method for Improving the Aircraft Hydraulic Drives Ability to Work

Abstract One of the approaches to ensure friction stability in hydraulic precise pairs can be coating their components with low-friction materials with the friction coating method using a metal, e.g. brass. The article presents the method of applying brass on the steel surface of a hydraulic pair using friction. It discusses the technology of brass plating of hydraulic precise pairs and the results of laboratory tests involving friction-brasses hydraulic precise pairs. The factors impacting the quality of brass-coating process of hydraulic precise pairs and the requirements set for hydraulic precise pairs subject to friction-brassing were also discussed.

Influence of Pulse Parameters on a b Cuzn Alloys Electrodeposited Coatings

Cu-Zn alloys is the most manufactured copper alloy in the word since it offers a wide range of properties depending on its zinc content. Although brass plating has been studied since 1841 by Ruoltz, and despite several studies devoted process improvement, CuZn coatings from non-cyanide baths shows low reproducibility, poor adhesion, inhomogeneous color and frequently cannot be deposited directly on steel. These problems are mainly attributed to an unusual crystalline phase distribution[1] [2]. Therefore, to obtain a higher quality of metallic electrodeposited alloy, it is mandatory to control the activity of the nobler ion in the solution, which is much more likely to be reduce. To that end, copper and zinc reduction potentials have to be bring closer by the use of a complexing agent of the copper ions. An electrolyte with a low citrate concentration has been developed and its electrochemical behavior extensively studied [3]. Varying Citrate concentrations will influence zinc electrodeposition and bath stability, giving the hand of the control of alloy element content. For the optimum conditions, CuZn coatings were obtained in a large range of Zn content (from 11% to 100%) as a function of Zn concentration and current density. Crystalline structures of the α β brass deposits were then identified in the range of 35% to 45% in Zn content, in order to be compared to commercial cast brass. The present study discusses the effect of pulse current for a selection of electrolytes, at the optimum of copper and citrate concentration. Wave modulation is investigated in order to compare Zn content and phase distribution for the same average current density. A particular focus was made on the quantification by XRD phase determination and its comparison with anodic dissolution. The best conditions have been tested on larger samples, to check adherence, homogeneity and to try to reach a maximum coating thickness and the right physical aspect than for the cast brass alloys. [1] J.C. Ballesteros, L.M. Torres-Martínez, I. Juárez-Ramírez, G. Trejo, Y. Meas, Study of the electrochemical co-reduction of Cu2+ and Zn2+ ions from an alkaline non-cyanide solution containing glycine, J. Electroanal. Chem. 727 (2014) 104–112. doi:10.1016/J.JELECHEM.2014.04.020. [2] T. Vagramyan, J.S.L. Leach, J.R. Moon, On the problems of electrodepositing brass from non-cyanide electrolytes, Electrochim. Acta. 24 (1979) 231–236. doi:10.1016/0013-4686(79)80030-4. [3] A. Dridi, L. Dhouibi, J.Y. Hihn, P. Berçot, W. Sassi, E.M. Rezrazi, Study of the influence of complexes stability on the kinetic of CuZn electroplating in a citrate bath, Submitted Electrochim. Acta. Figure 1

Organo-Chlorinated Thin Films Deposited by Atmospheric Pressure Plasma-Enhanced Chemical Vapor Deposition for Adhesion Enhancement between Rubber and Zinc-Plated Steel Monofilaments.

A continuous-flow plasma process working at atmospheric pressure is developed to enhance the adhesion between a rubber compound and a zinc-plated steel monofilament, with the long-term objective to find a potential alternative to the electrolytic brass plating process, which is currently used in tire industry. For this purpose, a highly efficient tubular dielectric barrier discharge reactor is built to allow the continuous treatment of "endless" cylindrical substrates. The best treatment conditions found regarding adhesion are Ar/O2 plasma pretreatment, followed by the deposition from dichloromethane of a 75 nm-thick organo-chlorinated plasma polymerized thin film. Ar/O2 pretreatment allows the removal of organic residues, coming from drawing lubricants, and induces external growth of zinc oxide. The plasma layer has to be preferably deposited at low power to conserve sufficient hydrocarbon moieties. Surface analyses reveal the complex chemical mechanism behind the establishment of strong adhesion levels, more than five times higher after the plasma treatment. During the vulcanization step, superficial ZnO reacts with the chlorinated species of the thin film and is converted into porous and granular bump-shaped ZnwOxHyClz nanostructures. Together, rubber additives diffuse through the plasma layer and lead to the formation of zinc sulfide on the substrate surface. Hence, two distinct interfaces, rubber/thin film and thin film/substrate, are established. On the basis of these observations, hypotheses explaining the high bonding strength results are formulated.

分析技術から見た 「黄銅めっき／ゴムの接着界面」

分析技術から見た 「黄銅めっき／ゴムの接着界面」

Rapid Stripping of Brass-plating on Fine Saw Wire by Triangle-type Multiple Magnetron Plasmas

To remove brass plating on fine saw wire, line-shaped magnetron plasma source has been newly developed. New type of multiple plasma sources has been developed by applying to multiple-triangle-type electrodes. The stripping effects were successfully established by using high density magnetron source with 20mm gap in an axially applied magnetic field. From the EDS analysis results of wire surface after plasma stripping during 30sec, it is clearly shown that Zn was removed after 10sec stripping and Cu after 30sec. (Fe:38.5%?97.7%, Cu:39.3%?2.43%, Zn:22.2%? 0.03%)

Optimisation of brass plating condition in plating of patented steel wire

The patented steel wire that is exclusively used for reinforcement of rubber products such as tyres and hoses is usually provided with a coating of brass alloy. Brass plating increases the fracture life during the drawing operation and also improves adhesion to rubber. In order to obtain suitable solution for brass plating with more efficiency and environmentally safer condition, this paper deals with the effect of free cyanide in plating solution, electroplating time and voltage on the quality and thickness of coating. The most suitable concentration of free cyanide was found as 5 g L−1. The ideal thickness of coating with maximum drawability is 2–3 μm and the optimum conditions for brass plating of wire has been achieved under voltage of 1·5–2 V, pH = 11 for 2–7 min, and temperature of 30°C. Also the mean adhesion strength between rubber and patented wire under optimum condition is ∼7·3 MPa.

Rational use of soluble anodes

The use of soluble copper anodes in the brass plating of wire is optimized. The selection of material for insoluble anodes is considered.

Influence of the Conditions of Zincate on the Electroless Brass Plating of Steel

In this work, we report that zinc flash film must be applied on a substrate of steel in order to activate the surface for electroless brass plating and the effect of this layer on the final properties of brass film. It was established that the color of the brass film is highly dependent on the conditions of the application of the zinc flash. We found that the mechanism of electroless brass deposition begins with the partial dissolution of the zinc flash film. It was also found that a brass coating with good adhesion properties is obtained when the conditions of the zinc flash bath are as follows: current density of 10 A/dm2, immersion time of 30−45 s, and bath temperature of 40 °C.

Work in the metal industry and nasopharyngeal cancer mortality among formaldehyde-exposed workers

Objective To investigate further the possibility that the large nasopharyngeal cancer (NPC) mortality excess among a cohort of formaldehyde-exposed workers may be related to occupational factors external to the study plant. Methods Subjects were 7345 workers employed at a plastics-producing plant (1941–1984) in Wallingford, Connecticut evaluated independently as part of a National Cancer Institute cohort study. Vital status for 98% of the cohort and cause of death for 95% of 2872 deaths were determined through 2003. Reconstructed worker exposures to formaldehyde were used to compute unlagged and lagged exposure measures. We computed standardized mortality ratios (SMRs) based on US and local county rates. In a nested case–control study we evaluated mortality risks from NPC and from all other pharyngeal cancers combined (AOPC) in relation to formaldehyde exposure while accounting for potential confounding or effect modification by smoking or external (non-Wallingford) employment. Job applications, Connecticut commercial city directories and a previous survey were used to assign subjects to three external job groups. Results We observed no new deaths from NPC and one additional AOPC death (pharynx unspecified) yielding, respectively, SMRs of 4.43 (7 deaths, 95% CI = 1.78–9.13) and 1.71 (16 deaths, 95% CI = 1.01–2.72). Five of seven NPC cases worked in silver smithing (including brass plating and other jobs related to silver or brass) or other metal work (including steel working and welding), and this type of work was relatively rare in the remaining study population (OR = 14.41, 95% CI = 1.08–82.1). For AOPC, we found a moderate increase in risk for other metal work (OR = 1.40, 95% CI = .31–5.1). Interaction models suggested that NPC and AOPC risks were not elevated in subjects exposed only to formaldehyde. Conclusions The results of our nested case–control study suggest that the large nasopharyngeal cancer mortality excess in the Wallingford cohort may not be due to formaldehyde exposure, but rather reflects the influence of external employment in the ferrous and non-ferrous metal industries of the local area that entailed possible exposures to several suspected risk factors for upper respiratory system cancer (e.g., sulfuric acid mists, mineral acid, metal dusts and heat). Our findings may also help to explain why the associations with formaldehyde and nasopharyngeal cancer reported in the 1994 update of the 10-plant NCI formaldehyde cohort study were unique to the Wallingford plant (Plant 1 in NCI study). Further updates of the NCI formaldehyde cohort study should include co-exposure data on silver smithing and other metal work for all study plants to help explain the unique findings for nasopharyngeal cancer in Plant 1 compared with the other nine plants.

Brass and bronze plating

Brass and bronze plating

Study of the effect of zincate on the deposit of brass in steels of low carbon

In this work, the results of the characterisation of an electroless brass film deposited on low carbon steel are correlated with the conditions of application of an intermediate zinc film. The results report that the best conditions of electroless brass plating are obtained when the zincate is done under current density of 7–10 A/dm², temperature of 40°C and with immersion time of 35–45 seconds.

Examination of Rubber-Brass Inter-Reacted Layer of Steel Cord by Cross Sectional TEM Observation

Abstract Cross sectional TEM observation was conducted with the aim of investigating the interfacial reaction of commercially manufactured steel cord and rubber during vulcanization. At the initial phase of the reaction, an inter-reacted layer was uniformly generated regardless of uneven brass thickness. As vulcanization progresses, the thickness of the interreacted layer becomes uneven, i.e. the thicker the brass plate, the thicker the inter-reacted layer becomes. Thus, the inter-reacted layer grows unevenly making a mirror image of the uneven brass plate, while a Zn-rich brass layer was formed between the brass plating and the inter-reacted layer.

Brass and bronze plating

Brass and bronze plating

Brass and bronze plating

Brass and bronze plating

Brass and bronze plating

Brass and bronze plating

Brass and bronze plating

Brass and bronze plating