Experience of Using Complex Modifiers to Increase Corrosion Resistance of Pipe Steels

The article presents the test results of complex microcrystalline modifiers containing calcium, barium, strontium, rare earth metals. Complex modifiers were used in the processing of steel for 17G1S-U pipes in order to reduce its contamination with non-metallic inclusions, including corrosive ones. The use of modifiers allowed to reduce metal contamination by non-metallic inclusions of all kinds. The most experimental non-metallic inclusions were obtained during metal processing with INSTEEL®5.1 and INSTEEL®9.4 modifiers. In addition, the use of experienced modifiers ensured the production of complex oxysulfides of calcium, cerium and lanthanum with low oxygen content and thermal expansion coefficients, which increases the corrosion resistance of steel.

Increasing of Corrosion Resistance for Metal Products of Livestock Premises

The purpose of the work was to identify and analyze the causes of corrosion destruction of metal products, used in conditions of animal keeping on farms of the agro-industrial complex, and to find effective methods of combating it. In order to increase corrosion resistance of metal products of livestock farms and complexes, it is proposed to use the developed preparation, which has fungicidal and anticorrosive properties simultaneously. The rate of metal products corrosion during the experiment was evaluated by the museum strain of Aspergillus niger fungi. The article describes the causes of fungal corrosion, the principle of its effect on metals; proposes an inhibitor of complex action for the control of electrochemical and bio-corrosion. The protection efficiency of metal products by the inhibitor was evaluated by the corrosion braking coefficient and the degree of protection. The effect of inhibitor concentration on the rate of low carbon steel bio-corrosion has been studied. It has been proven that the rate of corrosion processes decreased by 50 times, when exposed to a medium, contaminated with fungus spores, on metal samples treated with an inhibitor.

RESEARCH OF WAYS TO INCREASE CORROSION RESISTANCE IN REINFORCED CONCRETE CONSTRUCTIONS. PART 2

The article presents the results of the fi nal series of tests on the study of ways to increase the corrosion resistance of reinforced concrete structures with primary protection in the form of an addition of acetone-formaldehyde resin ACF-75 and with secondary protection with a two-component resin Binder EP 11 Tikso. An analysis of the change in the adhesion strength of secondary protection elements with a concrete surface after exposure to sulfuric and nitric acid, as well as the eff ect of the presence of a preliminary primer on a concrete surface on the intensity of adhesion change is presented. Conclusions are drawn about the possibility of using a two-component resin Binder EP 11 Tikso as a secondary protection against corrosion destruction of concrete in the process of reinforcing reinforced concrete structures operating in environments containing sulfuric and nitric acids.

Synthesis and Electrochemical Characterisation of Magnetite Coatings on Ti6Al4V-ELI

Titanium alloys have been widely employed in implant materials owing to their biocompatibility. The primary limitation of these materials is their poor performance in applications involving surfaces in mutual contact and under load or relative motion because of their low wear resistance. The aim of this work is to synthesis magnetite coatings on the Ti6Al4V-ELI alloy surface to increase corrosion resistance and to evaluate its electrochemical behaviour. The coatings were obtained using potentiostatic pulse-assisted coprecipitation (PP-CP) on a Ti6Al4V-ELI substrate. The preliminary X-Ray Diffraction (XRD) results indicate the presence of the magnetite coating with 8–10 nm crystal sizes, determined for the (311) plane. Using X-ray photoelectron spectroscopy (XPS), the presence of the magnetite phase on the titanium alloy was observed. Magnetite coating was homogeneous over the full surface and increased the roughness with respect to the substrate. For the corrosion potential behaviour, the Ti6Al4V-ELI showed a modified Ecorr that was less active from the presence of the magnetite coating, and the impedance values were higher than the reference samples without coating. From the polarization curves, the current density of the sample with magnetite was smaller than of bare titanium.

RESEARCH OF WAYS TO INCREASE CORROSION RESISTANCE IN REINFORCED CONCRETE CONSTRUCTIONS

The results of the first two series of studies of ways to increase the corrosion resistance of reinforced concrete structures with primary protection in the form of an additive of acetone-formaldehyde resin ACF-75 and with secondary protection with a two-component resin Binder EP 11 Tikso are presented. Studies have shown that the addition of ACF-75 leads to a significant increase in the strength of concrete. The results of laboratory tests have shown that the use of concrete with the addition of ACF-75 is unacceptable in reinforced concrete structures operating in environments containing sulfuric and nitric acids, without additional corrosion protection of the surface. In the course of the study, it was proved that the samples coated in three layers with Binder EP11 Thixo resin were resistant to a 5% solution of nitric acid.

INFLUENCE OF CORROSION INHIBITING PRIMER ON PROPERTIES OF THE GLUED JOINTS EXECUTED USING ORGANIC SILICON GLUE-HERMETIC

Properties of glued joints of D16-AT aluminum alloy with previously put adhesive priming covering EP-0214, received using glue-hermetic Elasil 137-175M are given. Stability of properties of glued joints, both without first coat, and with first coat EP-0214 is shown, is direct after pasting and after thermal aging at temperatures up to 250 °С, influences of water, tropical conditions. Application of priming covering allows to increase gap between anodizing and pasting operations and to increase corrosion resistance.

Pengaruh Rapat Arus Proses Continuous Hard Anodizing Elektrolit (H2SO4) terhadap Laju Korosi Pipa Aluminium 6061 dengan Pengujian Kabut Garam

Anodizing is an electro-chemical process used to coat metal surfaces with a stable oxide layer. The function of this oxide layer is to increase corrosion resistance. The purpose of this study is determine the effect of variations in current density on the continuous hard anodizing process carried out in sulfuric acid electrolyte solution (H2SO4) on the corrosion rate of aluminum alloy 6061. Corrosion rate testing is carried out through salt fog testing. The values of the current variation used are 1 A/dm2; 2 A/dm2; 3 A/dm2; 4 A/dm2; and 5 A/dm2. Statistical calculations using the analysis of variance proved the current density in the anodizing process has a significant effect on the corrosion resistance of the anodizing workpiece. Corrosion testing provides information that the highest corrosion rate is an anodizing workpiece with a current density of 1 A/dm2, which is 125.6861 mdd, then 2 A/dm2 of 104.33333 mdd. The lowest corrosion rate value obtained at the use of current density 3 A/dm2, that is 51,8083 mdd. Meanwhile, the use of current density of 4 A/dm2 has a slightly higher corrosion rate compared to the use of current density of 3 A/dm2, which is 86.5444 mdd. Furthermore, the use of current density of 5 A/dm2 has the highest decay rate, so that the formed oxide layer will be damaged, as seen from the higher corrosion rate of the material, which is 100.8361 mdd.