Papers by Keyword: Steel Protection

Abstract: This work aims to prepare an epoxy basalt powder and apply it as a protective coating for steel. Basalt powder was dispersed in epoxy resin with different doses of 3, 6, 9, and 12% of the epoxy weight. The prepared modified epoxy coatings were applied to the surfaces of carbon steel plates, and the coated samples were evaluated as follows: dry film thickness (DFT), adhesion strength, impact resistance, bending test, abrasion resistance, and fire and chemical resistance. The study revealed that using basalt powder improves the protective performance of epoxy. The obtained results showed that the optimum basalt content is 9%, and the enhancing coating performance of epoxy modified with 9% basalt as compared to neat epoxy was as follows: DFT increased by 50%, adhesion strength enhanced by 85%, and impact resistance increased by 95%. Abrasion and fire resistance were improved by 13% and 30%, respectively. Lastly, the chemical resistance of coatings was changed from fair to excellent. Keywords: epoxy, epoxy basalt coating, steel protection, basalt powder

Abstract: The silicate-enamel coating becomes the actual coating as a result of firing, which is a process of heating steel products coated with a “biscuit” dried slip layer, until completely melted, and a continuous coating is obtained on a metal substrate. With the constantly increasing requirements for the technical and operational properties of enameled products in the production of steel pipelines, it is advisable to use single-layer enameling, which saves raw materials and energy, due to the reduction in the number of layers and firing cycles of products. Its use for large-sized products, such as pipelines, eliminates their warping that occurs during repeated firing. In addition, the use of single-layer coatings makes it possible to obtain a better surface of products, since with a decrease in the resulting coating thickness it becomes more elastic and impact-resistant. All of the above is predetermined both by the structure of the glass coating itself and the generally formed steel - enamel composition. Therefore, knowledge of the structure, as well as of the physicochemical processes that occur during the firing of the enameled product, is necessary to solve technological issues successfully.

Abstract: The investigations on anodic oxidation of galvanic Zn-Ni alloy coating in the baths containing sodium hydroxide, sodium silicate and ammonium pentaborate was described in this paper. The surface morphology studies (SEM) and corrosion characterization was the main part of the work. It was found that the anodic treatment of the Zn-Ni alloy coating in the alkali solutions basis on NaOH permit to the obtaining the oxide layer with cracks formation. Application of the baths containing also sodium silicate and ammonium pentaborate cause the cracks decay. The corrosion studies may indicate that the cracks are shallow.