Brass Plating Research Articles

Brass and bronze plating

Brass and bronze plating

Noncyanide brass plating bath and a method of making metallic foil having a brass layer

Noncyanide brass plating bath and a method of making metallic foil having a brass layer

Fluorescence studies on the reduction of quinone by cyanide in aqueous 2-hydroxypropyl-β-cyclodextrin solutions

Water-soluble 2-hydroxypropyl-β-cyclodextrin was used to enclose 1,4-dibenzoquinone, 1,4-naphthoquinone, and 9,10-anthraquinone to form inclusion complexes. The inclusion complex of 1,4-dibenzoquinone was the most reactive of the three complexes in the presence of cyanide anion. The 1,4-dibenzoquinone inclusion complex reacted with cyanide anion to form a fluorescent product with stable excitation and emission maxima at 410 and 480 nm, respectively. Assuming one to one stoichiometry the formation constant for 2-hydroxypropyl-β-cyclodextrin and 1,4-dibenzoquinone was estimated to be 4 M −1. Formation of the inclusion complex did not enhance fluorescence yield but increased the rate of product formation in aqueous solutions. In the presence of excess cyanide the limit of detection for 1,4-dibenzoquinone was 0.006 mM with a linear range of 0.01 to 0.04 mM. For cyanide detection the linear range of the assay was 2 to 10 mM with a detection limit of 0.041 mM. Rate assays for cyanide possessed linear ranges from 0.041 to 12 mM. The reaction was used to detect cyanide in beverages, acetaminophen preparations and brass plating solutions.

Effect of surfactants on the corrosion of amorphous 76Ni‐24P alloy in neutral solutions

Abstract76Ni‐24P amorphous alloys have been electrodeposited from solutions containing sodium lauryl sulphate (SLS) and triton‐X 100 (TX‐100) to improve the surface quality of the specimens. Corrosion behaviour of electrodeposited amorphous alloys in sulphate and chloride solutions at 25°C has been studied by potential‐time decay, linear polarization resistance and potentiodynamic techniques. Anodic polarization curves show that the specimens exhibit mild passivity at potentials between approximately −200 mV and 200 mV (SCE) and dissolve transpassively above 200 mV (SCE). The sulphate solution was found to increase the dissolution of the samples treated by the surfactants during the substrate brass plating. The nonanionic surfactant increases the corrosion current by 10 times compared to the anionic one which enhances the current by 400 times; the interpretation was based on the enhanced dissolution of the microcrystals of the specimens in the sulphate solution and to the steric hindrance of the surfactants. In addition, the alloys are more resistant to chlorides due to the formation of a phosphate/hypophosphite film which protects the surface from dissolution.

Effect of surfactants on the Corrosion of amorphous 76Ni‐24P alloy in neutral solutions

Abstract76Ni‐24P amorphous alloys have been electrodeposited from solutions containing sodium lauryl sulphate (SLS) and triton‐X 100 (TX‐100) to improve the surface quality of the specimens. Corrosion behaviour of electrodeposited amorphous alloys in sulphate and chloride solutions at 25°C has been studied by potential‐time decay, linear polarization resistance and potentiodynamic techniques. Anodic polarization curves show that the specimens exhibit mild passivity at potentials between approximately –200 mV and 200 mV (SCE) and dissolve transpassively above 200 mV (SCE). The sulphate solution was found to increase the dissolution of the samples treated by the surfactants during the substrate brass plating. The nonanionic surfactant increases the corrosion current by 10 times compared to the anionic one which enhances the current by 400 times; the interpretation was based on the enhanced dissolution of the microcrystals of the specimens in the sulphate solution and to the steric hindrance of the surfactants. In addition, the alloys are more resistant to chlorides due to the formation of a phosphate/hypophosphite film which protects the surface from dissolution.

Structure of surface layers and wear resistance of quenched 50G steel after finishing, antifriction, nonabrasive treatment

The effect of the finishing, anti~ction, nonabrasive treatment (FANT) on the structure of the surface layer of the 50G steel subjected to quenching with rf heating without any friction is investigated. Ideas are formulated about the mechanism of formation of the surface layer. Structural parameters of the quality of the coatings determined by the method of nondestructive testing of the surface layers are presented, which can be used as criteria for rapid estimation of the conditions of technological surface treatment. The aggregate of tribotechnical properties of parts of cylindrical piston group including the wear resistance of linings, rings, and pistons, the coefficient of friction, breaking-in ability of the cylinder-lining--piston-ring pair, and the compatibility between the contacting metallic materials refer to factors that control the reliability and longevity of the internal-combustion engines. These properties can be estimated under service-, bench-testing-, and laboratory-testing conditions. A comparison between the results of laboratory tests using machines that produce reciprocating sliding with the wear data on linings and piston rings obtained during service [1 and others] showed that they were qualitatively in agreement, which indicates that it is expedient to estimate the tribotechnical properties in laboratory tests. These tests happen to offer unique possibilities for obtaining a separate estimate of the quality of a pair consisting of a cylinder--piston set needed for the substantiation of the approach toward the choice the structural and lubricating materials, the conditions of the technological processing of the surface parts leading to reduced losses by friction and wear. One of the methods of improving the tribotechnical properties of the parts of a cylinder--piston set is the brass plating or a finishing, antifriction, nonabrasive treatment (FANT) of the surface [2-4]. This treatment is also technologically simple, as well as effective in preventing seizure and decreasing friction and wear. However, according to the data of [4], depending upon the service conditions the effect of FANT may not even be manifest which gives us reaso~ to assume that a negative result is possible depending upon many factors, particularly the structural state of the treated material. Such cases were observed in practice during the service of internal-combustion engines. In this paper, based on the results of laboratory tests on the lining--ring friction pair, we have analyzed the changes in the structure of the surface layer of the quenched 50G steel subjected to FANT, their effect on wear resistance, as well the quality of the surface layer. Using a 77MT-1 reciprocating sliding-friction machine (at a pressure of 30 MPa and average velocity of 0.1 m/sec),

A flow through analysis biosensor system for cyanide

A flow through biosensor system has been developed for the determination of free cyanide in brass plating and rinsing solutions. The system consisted of rhodanese immobilized on aminopropyl glass beads via glutaraldehyde activation to form an enzyme column and sulfite oxidase immobilized on a preactivated nylon membrane and attached to the surface of a hydrogen peroxide electrode (platinum vs silver/silver chloride at 0.7 V). The immobilized rhodanese first converted cyanide to thiocyanate in the presence of thiosulfate and produced sulfite which was, in turn, converted to sulfate by immobilized sulfate oxidase. The latter enzymatic reaction also released hydrogen peroxide which was amperometrically detected at the platinum anode. The biosensor system exhibited a linear response from 5 to 1000 μM cyanide and could be reused for 35 repeated analyses. The system was stable for at least 18 h of continuous operation at 25°C. The immobilized rhodanese and sulfite oxidase stored in 3 M ammonium sulfate were stable for 4 months at −20°C and 50 days at 4°C, respectively. When measuring cyanide in metal plating solutions, the results obtained by the biosensor system agreed well with that of soluble enzymatic and the colorimetric assays. The data obtained, however, was not in agreement to those of the commercially available Orion cyanide electrode.

パルス電解法によるシアノ錯体浴からの銅‐亜鉛合金電析についての研究

Pulse plating of Cu-Zn alloy from cyanide brass plating baths was investigated with respect to the effect of pulse electrolysis with galvanostatic square pulses on the potential-current curves, current efficiency and composition of brass deposit. It was found that pulse plating yielded a brass deposit of uniform composition with a brighter appearance and finer crystal grain than that obtained under direct current electrolysis, and that the effect of pulse plating at a high pulsed-current density was mainly influenced by the increased deposition overpotential and the off period in each cycle where there is zero current in the external circuit. It was also noted that the electrodeposition mechanism changed from the regular type to the irregular type with increasing pH in the vicinity of electrode surface, since high pulsed current electrolysis resulted in a greatly increased hydrogen evolution reaction.

Effects of Salt Corrosion on the Adhesion of Brass Plated Steel Cord to Rubber

Abstract Adhesion loss caused by salt corrosion is proposed to occur by the following process: 1) During a salt corrosion test, the NaCl solution rises in the cavity located at the steel-cord center. 2) An electrochemical oxygen concentration cell is formed. 3) OH− is produced by the reduction of oxygen. 4) An increase of the NaOH concentration causes the reverse of ion tendency between brass and steel. 5) Dezincification and dissolution of brass take place in the brass plating. The same process also occurs in the corrosion of a bare brass plated steel cord immersed in NaCl solution. Compounds containing cobalt stearate and a compound free from cobalt show adhesion deterioration by the process described above. Many other cobalt salts suppress the corrosion of brass in NaCl solution. At the same time, the underlying steel changes to become ignoble compared with brass, leading to the production of a large amount of rust. In view of the above considerations, it is desirable to remove the cavity located at the steel-cord center in order to suppress the steel-cord corrosion. Use of an open type of steel cord is useful in this respect.

Determination of brass composition and plating thickness on brass‐plated wire and cord by x‐ray fluorescence spectrometry

AbstractThe control of brass composition and plating weight on brass‐plated steel wire and cord used as reinforcement in tyres is generally carried out by atomic absorption spectrometry, or by polarography. These methods require a mineralization of the sample and the analysis time is very long. On account of this, we have studied a direct analytical method on wires based on x‐ray fluorescence spectrometry. The mathematical method we use suppresses the influence of the cord construction and allows to calculate simultaneously the composition and thickness of the brass coating. The analytical performances, i.e. repeatability, accuracy and analysis time, are better than those prevailing with atomic absorption spectrometry or differential pulse polarography. Moreover, by dispensing with mineralization of the sample, XRFS is particularly well‐fitted for a routine control in production.

Configuration of the Brass on Brass-Plated Steel Wires in Tire Cords

Abstract Study of the brass configuration on wires from a number of cords from different sources shows that the brass on all of the wires is highly nonuniform in its distribution. It is not a “layer” as the word is generally understood. In some areas, the steel is almost bare; in some areas, brass coverage may be 0.1–0.2 µm thick; in still other areas there are “intrusions” of brass extending into the steel much more than a micrometer. It is believed that this brass configuration is typical of all steel wires which have been drawn after brass plating; hence, it is probably typical of all wires currently used in brass-plated steel tire cord. Consideration should be given to this erratic brass configuration in studies of adhesion of tire rubber to brass-plated steel tire cord. Perhaps the current model(s) should be modified to include the possible effect of the reservoirs of brass in the “intrusions” which exist in the steel.

AES investigation of diffusion formed brass coatings

The formation of brass plating by diffusing two separately electrodeposited layers of Cu and Zn was investigated by scanning Auger spectroscopy. The samples consisted of steel wires that were first plated with Cu and then Zn. The wires were heated by electrical resistance and quenched. The Auger analysis revealed significant differences between the diffusion brass and either bulk brass or alloy deposited cyanide brass. As the diffusion progressed as a function of time and temperature a relatively homogeneous layer of brass was observed to form in the outer region of the coating, while near the Fe substrate the plating remained Cu rich. The thickness and Cu concentration of the homogeneous layer as well as the relative amounts of α and β brass could be controlled in the diffusion process by adjusting the time and temperature of diffusion. A thick layer of ZnO was also detected on the surface of the coating. Various processing procedures for removing the ZnO including acid etching were investigated by AES.

A Curing System for Rubber Bonded to Brass-Plated Tire Cord

Abstract Devising a suitable vulcanizing system for steel cord carcass mixes presents unusual problems. A relatively high proportion of sulfur needs to be present to react with the brass plating, but this is not generally regarded as good compounding practice, particularly from the point of view of heat-aging resistance. If an attempt is made to improve matters by increasing the ratio of sulfenamide accelerator to sulfur, adhesion suffers. To help resolve these problems, it is suggested that the accelerator N-oxydiethylenebenzothiazole-2-sulfenamide is used in conjunction with dimorpholinyl disulfide. Good adhesion can be obtained with no more than 3.5 parts phr of sulfur and only a moderate amount of vulcanization activator, such as zinc stearate, is needed for maximum state of vulcanization. Insufficient work has been carried out to reach a position where a complete formulation can be recommended, but it is believed that the following vulcanizing system could be used as the basis for achieving a high standard of adhesive bond between a natural rubber tire carcass mix and brass-plated steel tire cord: (see PDF for table)

Brass Powder in Rubber Vulcanizates. The Effect on Adhesion

Abstract Brass plating is presently used for promoting the adhesion of rubber to steel cords used in tires. It is generally accepted that the adhesion is due to chemical bonds that are formed between the rubber and brass,1 although evidence has been obtained indicating that the adhesion is the result of a physical phenomenon.2 In addition, a catalytic oxidation theory also has been advanced.1 Natural rubber vulcanizates loaded with brass powder showed an increase in crosslinking (by swelling measurements), indicating an interaction or bonding between the rubber and brass. Techniques previously employed with reinforcing fillers such as carbon black were used to evaluate the effect of brass on adhesion. The addition of brass powder decreased the scorch time and optimum cure time indicating that the rubber immediately surrounding the brass was being cured at a faster rate. Copper powder, on the other hand, inhibited the cure completely. When exposed to air or oxygen, even small amounts of brass catalyzed oxi...

A rapid determination of brass composition and plating weight on brass-plated steel wire and cord by X-ray fluorescence spectrometry

A rapid and simple means for determination of the brass composition and plating weight on brass-plated steel wire and cord is described. The sample preparation procedure is very simple; wires can be mounted as such, and cords can be mounted either as such or as unstranded single wires. The copper content of the brass and the plating weight are determined by measuring the intensities of the different elements by sequential X-ray fluorescence spectrometry (XRF). There is good agreement between the results obtained by XRF and those obtained by differential pulse polarography or spectrophotometry/ complexometry; the precision is even better.

Effectiveness of emulsion KOS-1 in wire drawing

The starting material for metal cord production is carbon steel U7A. After lead potenting and galvanothermal brass plating, the 0.78-mmdiameter starting stock is drawn to a diameter of 0.15 mm in 18 passes on mills of the 22/200 UDZWG type. Drawing here is accomplished with the use of hard-alloy (alloy VK-6) draw plates up to 0.50-mm-diameter, or diamond draw plates (when less then 0.50-mmdlameter).

A comparison of the effects of sodium arsenite and sodium arsenoacetate upon the behaviour of a cyanide brass plating solution

The effects of 1 X 10 -2 m M additions of sodium arsenite and sodium arsenoacetate upon a brass plating solution have been studied. The arsenoacetate was found to be a better brightening agent than the arsenite. Potential-current density curve studies showed that the arsenide decreased cathodic polarisation but that the arsenoacetate increased polarisation. Both additions led to modifications of the structure of the deposited brass and to increases in its hardness. The colour of deposits obtained using sodium arsenoacetate additions varied considerably with deposit thickness.

A Rapid Direct X-Ray Fluorescence Method for Simultaneously Determining Brass Composition and Plating Weight for Brass-Plated-Steel Tire Cord Wires

AbstractA rapid direct x-ray fluorescence (XRF) method has been developed for simultaneously determining brass composition and plating weight for brass -plated-steel tire cord wires. On a manual XRF instrument, a complete analysis can be done in ten minutes including calculations. A complete analysis can be done in only two or three minutes on a multi-channel Quantometer-type instrument. The method can easily be adapted to “on line” use.Analysis is done directly on the “as received wires. Sample preparation is simple and non-critical with no surface pre-treatment of any kind required. Sample weighing and dissolution of the brass plating are entirely eliminated. Wire samples may be either stranded or unstranded. Rather large variations in sample size can be tolerated because of the ratio-type calculation system used. Analytical precision is high.Calibration curves were established by wet chemical, atomic absorption, and solution-XRF methods. No serious calibration problems were encountered because the plating is an alloy, or because count data were taken from round, non-flat samples. Low impurity levels of iron in the brass plating are shown to have an insignificant effect on the plating weight calibration curve.

Brass plating of steel billets for tube sheets

Brass plating of steel billets for tube sheets

Special adhesives for rubber bonding

AbstractSpecial adhesives for bonding of unvulcanized and vulcanized elastomers are discussed. Major emphasis is placed on adhesives and conditions for bonding of vulcanized elastomers. The decline of brass plating is reviewed. Various methods of adhesion testing are discussed and illustrated. Available organic polymer based adhesives will produce high strength bonds to a wide variety of unvulcanized olefinic elastomers. A single coat adhesive has been developed which provides “maximum performance adhesive bonds” to a variety of unvulcanized elastomers. Factors affecting bonding and “bondability index” for the common elastomers are described. The bonding of vulcanized elastomers is a more difficult task. Present adhesives require mechanical or chemical modification of the surface of the elastomer. Brute force tactics used in conjunction with epoxy‐polyamide, phenolic‐polyvinyl formal, or nitrilephenolic systems have performed well in some applications. The quality of these bonds, however, does not equal those produced to unvulcanized elastomers. With cooperation of the users, the adhesive suppliers are developing newer, more effective products to meet the challenge of the advanced polymers and increasingly severe environments in which they are used.