corrosion resistance

The article presents the results of research on cementitious systems "Portland cement CEM I 42,5 R - active mineral additives - microfillers - superplasticizer - hardening accelerators" for high-performance concrete with improved corrosion resistance. The resistance of concrete to corrosion caused by the influence of chemical substances was investigated - sulfate corrosion (class XA), which combines the processes of formation and accumulation of sparingly soluble salts in concrete, which are accompanied by internal stresses and destructive phenomena in concrete.

This paper describes the synthesis of geopolymer materials using thermally modified clay rocks of Georgia and metallurgical granulated blast-furnace slag; as well as the study of their physical and mechanical properties, durability, and corrosion resistance in aggressive solutions.The methods of chemical, X-ray phase, differential thermal analysis and SEM were used.

The influence of surface-modified titanium dioxide on the electrochemical features of epoxy compositions was researched. The raise of epoxy primer protective properties by the presence of surface-modified fillers in its composition was determined. It is shown that the mechanism of the modified filler protective effect in epoxy coating applied on the steel is similar to the effect of solid zinc phosphate which effectiveness corresponds to the level of the known inhibitory pigment.

The corrosion resistance of steel with modified inhibitory pigments and polyurethane protective coatings was studied by impedance and electrochemical methods. It was found that the combination of a mixture of molybdate / zinc phosphate and calcium silicate in the polyurethane soil due to the synergistic effect enhances its protective properties. Impedance studies have confirmed the increase in anti-corrosion characteristics of such a system.

Influence of different types of surfactants on electrodeposition of copper- and carbon-bearing (graphite, carbon nanotubes (CNTs)) composite powder has been experimentally investigated. The size of powder particles decreased, and corrosion resistance increased when surfactants were added. Addition of cationic surfactant CTAB to the electrolyte with simultaneous ultrasonic treatment for CNTs dispersion gives maximum effect.

The principles and example of multicriterion structural and parametric optimization of the functionally-oriented technological machining process of mold’s parts hardened surfaces are described in the article. The most essential criteria of optimization are wearproofness, fatigue strength, contact stiffness and corrosion resistance of production. methodology of researches and algorithm of optimization are shown in the article.

The article describes the effects of surface treatment of concrete protective coatings filled of polimetylfynilsyloksan based on its corrosion resistance. The influence of the coating on the adhesive strength, hydrophobicity and water absorption of concrete. The possibility of using the developed formulations of protective coatings to improve durability of concrete is showed, which is operated under conditions of external aggressive factors.

The use of nitrogen as an alloying element presents a great interest for the improvement of properties of alloyed steels and special alloys. Superficial layers were formed by ionic implantation and by melting the surface by nitrogen plasma. After this kind of treatment, there form a continuous defect-free layers with a good adhesion to the surface. Surface treatment of steels and vanadium alloys increases their corrosion resistance and microhardness of surface layers.

The kinetic mechanism of cobalt-silver and cobalt-tungsten alloys electrodeposition from citrate-pyrophosphate and citrate electrolyte correspondingly has been established. The influence of electrolyte component ratios as well as polarization pulse on/off time ratios on cobalt alloy composition and its current efficiency has been determined. The cobalt-silver and cobalt-tungsten alloys have been shown to possess catalytic and anticorrosion properties.