| Abstrakt: |
Investigation of the regularities of anodic oxidation of stainless steel in acid solutions is important because they have practical significance in technologies such as surface treatment of materials and electrochemical protection against corrosion of metals and alloys. The purpose of this work is to investigate the effect of electrolyte content on anodic dissolution of stainless steel, morphology, microhardness, electrical insulation resistance and overall impedance of oxide coatings. The kinetics of the anodic dissolution process was investigated by the method of linear voltammetry in a potent dynamical regime at a rate of scan potential of 2 mV⋅с–1. Microhardness was determined using a microtome meter PMT-3 and computer processing of results. The electrical insulation resistance of oxide coatings was measured by the E6-13A thermometer. Anodic polarization dependences obtained from molybdenum, zirconium, aluminum, titanium containing electrolytes showed that the compounds introduced into sulfate and sodium chloride increase the anode currents in the active region, expand the active dissolution region and increase the passive region that is the basis for the formation protective oxide films on stainless steel. The morphology studies have shown that the addition of valve metal compounds to the sulfate solution and sodium chloride, such as molybdenum, titanium, zirconium, and aluminum, leads to a decrease in the size of the globules on the surface of the steel. It is proved that oxidation of steel reduces the microhardness of coatings. The protective properties of oxide coatings on steel obtained by anodic oxidation were investigated by the method of impedance spectroscopy. It was found that the introduction of compounds of molybdenum, zirconium leads to a sharp increase in the electrical resistance of the insulation, therefore the resulting coatings exhibit high dielectric properties. [ABSTRACT FROM AUTHOR] |
