Corrosion Resistance Of Brass Research Articles

Synergistic effect of water solubility sulfhydryl compound and rare-earth ions on the microstructure, composition, and corrosion resistance of brass

The aim of the present research is to develop one new strategy to modify the brass surface with well anticorrosion performance. Here, utilizing the synergistic effect between thioglycolic acid (TGA) and Y(III), one organic–inorganic hybrid film composed of a self-assembled film at the top and an oxide film at the bottom was fabricated on brass surface. The formation process of the hybrid film contained the parallel adsorption of TGA molecules, surface oxidation of copper accompanied by zinc dissolution, interface deposition of Y2O3 and assembly of Cu-TGA chelates. Electrochemical results indicated that the protection efficiency was 99.2% under the optimum conditions and the value remained at 92.1% after 12 h immersion in 3.5 wt% NaCl solution. Due to the good water solubility of the film-forming substance and excellent anticorrosion performance of the fabricated film, this strategy has important application potential in the field of surface functionalization of copper alloys.

MODIFICATION OF THE SURFACE OF COPPER ALLOYS WITH ALUMINUM IN THE CONDITIONS OF SELF-PROPAGATING HIGH-TEMPERATURE SYNTHESIS

The influence of the technological parameters of the SHS process (temperature, holding time and alloying of B, Cr, Ti) on the corrosion resistance of brass with a surface alite layer, which effectively resists β-radiation, was studied. The research was carried out in 30% aqueous solutions of HNO3, HCl, H2SO4. Aluminized coatings doped with silicon, which are obtained under optimal parameters, have 1.7-2.1 times higher corrosion resistance than doped B and Ti. Alloyed coatings have phases CuSi, CuAl, CuAl2, CuTi, Ti2Cu3, CuCr, Cu3Al, Cu2Al, Al3Si, and α-phase doped with Cr, Al, Si, B, Ti. When tested in a 30% aqueous solution of nitric acid, the coating doped with titanium and silicon shows a weight loss of 32 and 37 g/m2, respectively.

Effects of TiO₂ Nanofluid on the Surface State of Brass.

The surface states of brass in simulated cooling water (SCW) containing or free of sodium dodecyl benzene sulfonate (SDBS) and TiO2 nanofluid were analyzed by means of scanning electron microscope (SEM), energy spectrum analysis (EDS) and X-ray diffraction (XRD). The concentrations of Cu and Zn ions in the solution after brass immersion were analyzed using a plasma emission spectrometer. The relationship between the surface states and corrosion resistance of brass was investigated by electrochemical impedance spectroscopy (EIS). The results showed that the brass surface was mainly covered with zinc compound Zn5(OH)6(CO3)2 as corrosion product in SCW. In SCW containing SDBS, a large amount of SDBS was adsorbed on the brass surface. In TiO2 nanofluid, the brass surface was relatively bare and mainly contained cuprous oxide. There was no obvious adhesion of SDBS aggregates and no accumulation of zinc compound on brass surface in TiO2 nanofluid. TiO2 nanoparticles inhibit the adsorption of SDBS on brass surface. Solution analysis results showed that the concentrations of Cu and Zn ions in TiO2 nanofluid was obviously higher than that in SCW and SCW containing SDBS, indicating that most of corrosion products of brass dissolved into the nanofluid. The EIS results illustrated the brass electrode had a larger reaction resistance in SCW containing SDBS, indicating the good protective performance of the adsorbed SDBS film on brass surface. The reaction resistance of the brass electrode was the smallest in TiO2 nanofluid, which illustrated that TiO2 nanoparticles in solution promoted the corrosion of brass.

Influence of Al2O3 nanoparticles on the corrosion behavior of brass in simulated cooling water

The influence of Al2O3 nanoparticles on the corrosion behavior of brass in simulated cooling water (SCW) with or without sodium dodecyl benzene sulfonate (SDBS) was investigated by means of electrochemical impedance spectroscopy, polarization curves, scanning electron microscope, energy spectrum analysis, X-ray diffraction and Fourier transform infrared spectroscopy. Results indicate that the brass suffered severe corrosion in SCW and the SCW-Al2O3 nanofluid. The main corrosion product was Zn5(OH)6(CO3)2. Al2O3 nanoparticles promoted both anodic and cathodic processes in the brass electrode, and dezincification was most serious in the SCW-Al2O3 nanofluid. The adsorption of SDBS on the brass surface was enhanced, and a more compact protective film was formed on the brass surface in the SCW-Al2O3-SDBS nanofluid. As a result, the corrosion resistance of brass was increased in this medium.

The effect of alloying elements on the corrosion resistance of brass

A systematic study has been performed on the effect of alloying elements arsenic (As), antimony (Sb) and phosphorus (P) on the dezincification resistance of α-phase in brass. The result showed that P formed particles with Al and Fe already at relatively high temperatures, leaving no P in solid solution and thus no protection against dezincification. Arsenic only formed particles at lower temperatures and offers a satisfactory protecting. However, with increasing As levels grain boundary attack was observed. Samples alloyed with Sb show a satisfactory resistance to dezincification and no grain boundary attack. Finally, a combination of As and Sb at low alloying levels provided an excellent dezincification resistance for brass containing typical impurity levels.This paper is part of a Themed Issue on Brass Alloys.

Evaluation of the Influence of Fossil Fuel on Corrosion Resistance of Brass

Brass is an excellent material choice for use in most industrial and agricultural application. Brass offers much better thermal conductivity and corrosion resistance than carbon or even stainless steel. Brass is an excellent material for use in both hot and cold water industrial and residential system including those carrying portable water. This study was carried out to investigate and evaluate the influence of fossil fuel like petrol, kerosene and diesel on the corrosion performance of brass. The samples were prepared for the study by cutting brass into 1 cm2 coupons and soaking them in different small plastic containers containing petrol, kerosene and diesel. The corrosion rate of each sample for a specific period of immersion (120, 240, 360, and 480, 600 and 720 hours) was determined on average of three samples exposed under the same condition and test media in different container. The finding showed that brass is resistant to corrosion after long hours of contact in chosen liquid fossil fuels. Brass has the highest corrosion rate in petrol, followed by kerosene and least in diesel. The photomicrographs of the samples after ten days of immersion also confirmed this.

Thermodynamic evaluation of corrosion-electrochemical behaviour of silicon brass CuZn17Si3

The thermodynamic activities of brass CuZn17Si3 components are calculated. The potential-pH diagrams for the brass CuZn17Si3-H2O system for 25°C, a total air pressure of 1 bar, and various ions activities in solution are plotted. The thermodynamic features of the chemical and electrochemical stability of brass CuZn17Si3 are analyzed. It is shown that high corrosion resistance of brass is achieved with respect to the formation of a protective film of ZnSiO3 on its surface.

Study on Corrosion Resistance of Brass in Circulating Cooling Water with Different Concentration Ratio

Abstract: The corrosion resistance of brass H70-1A cooling water was studied through weight-loss method and electrochemistry measurement in different concentration ratio condition. The results obtained from this study showed that brass inhibitor was necessary to add to circulating cooling water system when concentration ratio was in the range of 3~7.

Effect of High Pressure Heat Treatment on Microstructure and Corrosion Resistance of Brass

Effects of high pressure heat treatment on the microstructure refinement and corrosion resistance of brass were studied by means of metallographic observation, SEM/EDX, profilometer and CH1660A electrochemical instrument. Brass were heated from 23°C to 700°C and kept at 700°C for 10 minutes under high pressure of 1GPa, 3GPa, 4GPa and 6GPa, respectively. The results show that high pressure heat treatment has great influence not only on the microstructure refinement of the alloy but also on its corrosion resistance in HCl solution. Under 3GPa, the refined microstructure can be found and the corrosion resistance of the alloy changes into much worse. However, under a higher pressure of 6GPa, the corrosion resistance increases and the microstructure refining effect is not obvious. All the findings of this work were elucidated in terms of the change in the formation and growing of the crystal under a high pressure heat treatment condition.

Electrochemical studies on the corrosion of brass in seawater under anaerobic conditions

This paper reports an electrochemical study on the corrosion of brass in deoxygenated nonbuffered and buffered natural and artificial seawater solutions under anaerobic conditions. Cyclic voltammograms of brass and copper in natural seawater (NSW) and artificial seawater (ASW) were obtained in the passive and transpassive potential regions. The corrosion resistance of brass in natural and artificial seawater was evaluated, and open-circuit potentials were recorded over exposure period of 1 week. Brass samples from 3-month exposures in deoxygenated nonbuffered ASW and NSW, under open-circuit potential, have been imaged by scanning electron microscopy, and the elemental composition of the corrosion products was obtained by energy dispersive spectrometry analysis. It has been concluded that, under anaerobic conditions, the aggressivity of NSW is higher, with brass being less resistant to corrosion than copper, and that buffer contributes to reduce the aggressivity of both media.

A comparative analysis of copper and brass surface films in contact with tap water

A study of the surface oxide films naturally grown on copper and brass in contact with drinkable water is presented. The investigation focuses on the influence of Zn as alloying element on the corrosion resistance of brass. Artificial tap water, employed as electrolyte, simulates a practical application of these materials. The surface films were grown at open circuit potential for 2 and 192 hours. Diverse in-situ techniques such as cyclic voltammetry, polarization curves, electrochemical impedance spectroscopy and UV-Vis reflectance spectroscopy were employed. Even when the surface layer is mainly composed of cuprous oxide, Zn(II) species are incorporated in the surface film grown on brass. At longer ageing times, the thickness increases, without affecting the composition of the surface films. The corrosion current was calculated for both materials using various techniques. The corrosion current density and the anodic currents in the polarization curves decreased as the ageing time increased, particularly in the case of brass. This improvement in the performance of the film on brass can be attributed to the incorporation of Zn(II) species into the surface layer, particularly as the film consolidates at longer times.

A study of pulsed plasma oxidation effects on the corrosion resistance of brass

The plasma oxidation process and the corrosion resistance mechanism of oxidized (α+β) brass (65Cu35Zn) in pulsed dc oxygen plasma and Mattson's solution are reported. The brass was exposed to pulsed DC oxygen plasma with various pulse frequencies. When the brass was exposed to the oxygen plasma, ZnO was identified dominantly in the passive layer and α-brass sublayer was formed because Zn in the (α+β) brass diffused to the surface. These multi-passive layers contribute to the corrosion resistance behavior of (α+β) brass with 92.5% corrosion protection efficiency for the untreated sample. But as input pulse frequency decreases, it becomes more effective in corrosion resistance and has relation with surface behavior in corrosion processing.

Enhancement of cavitation erosion and corrosion resistance of brass by laser surface alloying with Ni–Cr–Si–B

Brass (Cu–38% Zn–1.5% Pb) was surface-alloyed with a hardfacing Ni–Cr–Si–B powder (Ni–16.5% Cr–3.5% Si–3.8% B–15.5% Fe–<1% C) using a high-power continuous-wave Nd-YAG laser with different processing parameters for improving the cavitation erosion and corrosion resistance in 3.5 wt.% NaCl solution. The cavitation erosion resistance R e (defined as the reciprocal of the mean erosion rate) of the alloyed layer ranged from 6.10- to 9.06-fold that of the brass substrate, and was found to be closely related to the hardness of the alloyed layer. The corrosion resistance was also improved, as indicated by a noble shift in the pitting potential and a reduction in the corrosion current density. The difference in the cavitation erosion and corrosion behavior of various specimens is discussed in relation to their microstructures and structures via studies using optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX) and X-ray diffractometry (XRD). The present study also indicated that it is difficult to achieve maximum improvement in cavitation erosion and corrosion resistance simultaneously.

Improvement Of Cavitation Erosion Resistance and Corrosion Resistance Of Brass by Laser Surface Modification

AbstractLaser surface modification of brass (Cu-38Zn-1.5Pb) using AISiFe and NiCrSiB alloy was achieved by using a 2kW continuous wave Nd-YAG laser with the aim of improving the cavitation erosion resistance and corrosion resistance. The alloying powder was preplaced on the brass substrate by thermal spraying to a thickness of 350µm, followed by laser beam scanning to effect melting, mixing and alloying. A modified surface was achieved by overlapping of adjacent tracks. The cavitation erosion resistance and the anodic polarization characteristics of the laser surface modified specimens in 3.5% NaCI solution at 23°C were studied by means of a 20kHz ultrasonic vibrator at a peak to peak amplitude of 60µm and a potentiostat respectively. The cavitation erosion resistance of the specimens modified with AlSiFe and NiCrSiB was improved by a factor of 3 and 7 respectively, compared with that of the brass substrate. Potentiodynamic test, however, indicated that the corrosion resistance of specimens modified with AlSiFe deteriorated, as reflected by a shift of the polarization curve towards higher current densities. On the other hand, the corrosion resistance of specimens modified with NiCrSiB was significantly improved, as evidenced by the presence of a passive region (from −175 mV to −112 mV) and a reduction in the anodic current density by at least an order of magnitude compared with the substrate at the same anodic potential. The hardness profile and the compositional profile were measured using a Vickers hardness tester and EDX respectively. The microstructure and the surface morphology of the specimens were investigated with the aid of SEM and optical microscopy.

Corrosion resistance of brass welded joints in acid and alkaline media

Corrosion resistance of brass welded joints in acid and alkaline media

Investigation of the corrosion resistance of brass in a dipterex solution

1. Brass undergoes preferential corrosion in a Dipterex solution. The solution most strongly attacks brass with an inhomogeneous structure of α and β phases.