Influence of technological processes MDO on porous and corrosion resistance of the alloy systems Al-Mg-Sc

One of the most important problems in the industry by using metals and alloys gate groups, which include aluminum alloys, is to increase the physical and mechanical properties, corrosion resistance of structures, components and assemblies made therefrom. Aluminium alloys, including Alloy 01570 have high specific physical and mechanical properties, but in solution or vapor salts have low corrosion resistance. To improve the corrosion resistance of the various protection methods are used, for example by forming a coating on the working surfaces. For the application of protective coatings on aluminum alloy 01570 a method of micro-arc oxidation (MAO) is proposed. The morphology operation research, payment of porosity and corrosion resistance MDO coatings were carried out. Aluminum alloy is characterized by pitting, turning from time to intergranular. In order to avoid penetration of the active corrosion-protection-through pores MAO coating to the surface of the aluminum alloy, it is necessary to obtain coatings with minimal porosity of the oxide layer. It is found that with increasing ratio of the anodic and cathodic current of from 0.8 to 1.2, a decrease of the total porosity. To determine the corrosion resistance of the coating formed, accelerated laboratory tests were carried out according to GOST 9.308-85 (Method 9). The process of corrosion failure is artificially accelerated, due to alternating samples immersion in corrosive media and then dried at room temperature. Quantitative analysis using a gravimetric method for determining the corrosion rate in simulated marine environment showed that the loss of weight is negligible and the estimated depth index coatings obtained by oxidation on the alloy microarc 01570 are completely resistant group.