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The purpose of this study was to compare the electrodeposition behavior and corrosion resistance of ternary and binary alloys.

Potentiodynamic polarization resistance measurement and anodic linear sweep voltammetry techniques were used for the corrosion study. The surface morphology and chemical composition of the deposits were examined using scanning electron microscopy and atomic absorption spectroscopy, respectively. The phase structure was characterized by X-ray diffraction analysis. Electrodeposition behavior was carried out using cyclic voltammetry and galvanostatic techniques.

It was found that the obtained ternary alloy exhibited better corrosion resistance and a more-preferred surface appearance compared to the binary alloys that were electrodeposited under similar conditions.

The ternary alloy showed better anticorrosion properties compared to binary deposits that were electroplated successfully from the plating baths. The Zn-Co-Fe alloy could be used advantageously in industry because the ternary alloy exhibits the collective properties of the binary alloys in one alloy via the electrodeposition of Zn-Ni-Co alloy.

Increasing the corrosion resistance implies to social economic increases.

To date, the electrodeposition of Zn-Co-Fe alloy was studied in only a small number of articles. It was found that the presence of Co or Fe could provide a useful coating on the steel that would reduce its susceptibility to corrosion attack.

One of a series of papers presented at a Symposium “Designed with Thermal Spraying in the '80s” organised by the Association of Metal Sprayers at the Europa Hotel, London W.1 on 22 April, 1982.

After a short description of the primary sources, the coverage, the file structure and the data elements of a PASCAL record, this article reviews how to search the database with MISTRAL software on QUESTEL, the French national host. It outlines with the help of simple search examples the software possibilities (truncation, mask, text searches …) and the loading parameters of the file (searchable fields, output formats …)

The purpose of this paper is to report salt spray testing of epoxy‐polyester top‐coating applied on Zn‐sprayed, Al‐sprayed and 85Zn‐15Al‐sprayed steel samples.

In these tests, steel substrates sprayed with Zn, Al and 85Zn‐15Al coatings of different average thicknesses ranging from 120 to 210 μm were top‐coated with an epoxy‐polyester sealing layer. The corrosion test was performed with salt solution for over 2,000‐h. The degree of damage to the samples was evaluated quantitatively in terms of ratio of scribed to unscribed area of coating.

It was evident that the corrosion resistance of Al‐sprayed top‐coated surfaces was better than coated Zn‐spray or coated 85Zn‐15Al‐spray systems. As a result, when Al‐coated surfaces were top‐coated with polymeric layer, it was found that their surfaces were remarkably unaffected by the salt spray environment.

The salt spray measurements indicated that the Al‐spray epoxy‐polyester polymer double system was more durable than the other two systems (polymeric top‐coated Zn‐spay, and polymeric top‐coated 85Zn‐15Al‐spray), so far as protection from the chloride salt spray environment was concerned.

Summary This paper describes an electrochemical procedure useful to the determination of metallic and oxidised parts in zinc‐base coatings obtained by thermal spraying. The procedure has been successfully applied to the examination of coatings made of pure zinc or of a zinc alloy containing 15% in weight of aluminium, as well as on corroded as on uncorroded samples. The method allows the degree of advancement of oxidation in the coating to be determined as a function of the exposure time; this permits an evaluation of the corrosion resistance to be made without having to wait for the appearance of rust on the protected steel plate. By this manner, the better resistance of the studied alloy compared to the pure zinc has been evidenced under severe conditions of attack by an aerated 5% NaCl solution. This could be attributed to a decrease in the oxidation rate of the metallic zinc in the alloy, owing to its higher aptitude to self‐sealing. The improved behaviour of the alloy has been attributed to the existence through the whole thickness of the coating of a coherent network made of an α‐aluminium‐rich phase, this explanation being in good agreement with the results of other investigations carried out by SEM + EDAX or by X‐Rays diffraction techniques, which have been reported elsewhere. Each studied coating was obtained from wires produced by Vieille‐Montagne under the trade‐names Zinacor 100 (pure electrolytic zinc) and Zinacor 850 (zinc‐base alloy containing 15% aluminium).

The selective laser melting (SLM) technique, as a typical additive manufacturing process, is widely used for the fabrication of metallic biomedical components. In terms of biodegradability, zinc and its alloys represent an emerging generation of metallic materials for biomedical implants. The purpose of this paper is to obtain the Zn and Zn10Mg alloys with high mechanical properties using the SLM technology. The relationship between the processing parameters and the porosity of pure Zn and Zn10Mg alloy samples was investigated.

The samples were fabricated using SLM technology working in an inert gas closed chamber. Preliminary experiments were conducted to analyze the laser power and gas flow on evaporation, single track form and porosity. To evaluate the influence of factors on relative density, the response surface methodology was applied.

The satisfactory results of the proposed method were achieved, in which the relative density of the components reached up to 99.63%, and compression strength reached 214 ± 13 MPa under optimal processing conditions.

Zinc is categorized by its low melting and boiling point, which leads to the high porosity of the components. It is difficult to prepare the Zn alloy samples with high relative density using SLM technology. This work successfully achieved dense Zn and Zn10Mg samples and investigated their microstructure, mechanical properties and corrosion behavior.

Based on the advantages of conventional hot-dip galvanizing made from quasi-pure zinc melts in the event of fire, this article aims to perform a series of tests to verify whether a similar effect can be achieved with zinc-aluminum coatings.

The emissivity of galvanized surfaces, which were applied to steel specimens by the batch hot-dip galvanizing process, was experimentally determined under continuously increasing temperature load. In addition to a quasi-pure zinc melt serving as a reference, a zinc melt alloyed with 500 ppm aluminum and thin-film galvanized with a melt of zinc and 5% aluminum were used. For the latter, variants of post-treatment measures in terms of a passivation and sealing of the galvanizing were also investigated.

The results show that lower emissivity can be achieved at higher temperatures by adding aluminum to the zinc melt and thereby into the zinc coating. The design values required for the structural fire design were proposed, and an exemplary calculation of the temperature development in the case of fire was carried out based on the values. The result of this calculation indicates that the savings potential becomes apparent, when using zinc-aluminum coatings.

The presented novel tests describe the behavior of zinc-aluminum coatings under the influence of elevated temperatures and their positive effect on the emissivity of steel components galvanized by this method. The results provide valuable insights and information on the performance in the event of fire and the associated potential savings for steel construction.

This paper aims to investigate the corrosion behavior of zinc in a typical hot and dry atmosphere. It proposes the dynamic corrosion for different exposure periods. Results can provide the basic data and corrosion mechanism of zinc in such environment.

In this paper, the authors investigated the corrosion behavior of pure zinc exposed in the typical hot and dry environment in Turpan for one-four years, which has never been studied. Scanning electron microscopy, laser scanning confocal microscopy, electron probe micro-analyzer (EPMA), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were conducted to measure the corrosion morphology and products of zinc. Finally, combining electrochemical impedance spectroscopy and scanning Kelvin probe techniques, the corrosion mechanism of zinc in Turpan was examined.

The thickness loss of the zinc followed an exponential law with respect to exposure time: D = 3.17 t^0.61, and both of the rust layer resistance and the charge transfer resistance increased with exposure time. The corrosion products mainly comprised ZnO, Zn(OH)₂, Zn₅(CO₃)₂(OH)₆, Zn₄SO₄(OH)₆·5H₂O and Zn₁₂(SO₄)₃Cl₃(OH)₁₅·5H₂O. The Kelvin potentials shifted toward the positive direction from −0.380 to −0.262 V (vs saturated calomel electrode [SCE]) when the exposure time extended from one to four years and the distribution of the corrosion products became more and more uniform.

The corrosion behavior of pure zinc in the typical hot and dry environment in Turpan has not been studied. The dynamic corrosion for different exposure periods was obtained. The corrosion products were systemically investigated via energy-dispersive X-ray spectroscopy, EPMA, XPS and XRD.

The purpose of this paper is to report the use of zinc phosphate pigment as a chromate substitute for coatings on non‐ferrous metals (galvanized steel, pure aluminum, α‐brass and pure copper).

Paint systems based on zinc chromate and zinc phosphate pigments were prepared. The paints were tested for their physico‐mechanical properties. Testing of the anticorrosive properties of the zinc phosphate pigment in comparison with zinc chromate pigment was carried out by accelerated corrosion exposure, i.e. immersion in 3.5 percent salt solution and exposure for one year at five outdoor stations.

The possibility of replacing chromate pigment was assessed and the “gap“ observable between the performance of zinc chromate and zinc phosphate pigments was noted.

The non‐toxic inhibitive pigment, zinc phosphate, incorporated into a plasticized‐chlorinated rubber binder, could be applied successfully for the protection of non‐ferrous substrates.

Electrical industry equipment in the southern parts of Iran have sustained severe damages as a result of corrosive soil containing different kinds of salt, in combination with the corrosive local atmosphere. The present paper is the result of investigations into the behaviour of coatings for various electrical insulators end‐fittings. In this research, the performance of Al‐Zn alloy coating was compared to conventional galvanized zinc coatings by means of atmospheric corrosion tests. The results demonstrated the higher corrosion resistance of the alloy coatings, compared to that of conventional galvanized coatings. Insulator end‐fittings generally are made of steel, which are coated with a hot‐dip galvanized coating. The combination of Al and Zn elements in this coating was demonstrated to possess better galvanic protection and lower corrosion rate than did pure zinc.