Magnesium alloys are now widely used for various purposes due to their unique properties despite the significant disadvantage associated with low corrosion resistance. The plasma-electrolytic oxidation (PEO), which allows the formation of ceramic coatings on the surface of magnesium alloys, is the most advanced and effective method for their protection. But firstly, PEO process of magnesium alloys has some difficulties, and secondly, PEO coatings affect the thermophysical characteristics of the modified materials, in particular they reduce thermal diffusivity. The presented work is devoted to the development of the technological parameters for formation of protective coating on the ultra-light alloy Mg-8Li-1Al-0.6Ce-0.3Y by the PEO method. The results analyses of electrolytes acidity and specific electrical conductivity before and after PEO process and also investigation data of the coatings structure and surface morphology are presented. An integral assessment of the ability of thermal diffusivity and corrosion resistance of the modified alloy was made. Studying of protective and thermophysical characteristics of the obtained coating showed that it provides a sufficiently high corrosion protection, despite the relatively small thickness, and the presence of pores and slightly (not more than 5%) reduces the thermal diffusivity of the magnesium ultra-light alloy.

The electrochemical formation of ceramic-like coatings on D16 aluminum alloy was carried out using microarc oxidation method in phosphate (1.5 g/L NaOH + 9 g/L Na2SiO3 + 3 g/L Na3PO4) and molybdate (5 g/L NaOH + 30 g/L Na2SiO3 + 5 g/L (NH4)6Mo7O24) electrolytes. White and black ceramic-like coatings with thickness of 200–300 microns were obtained in phosphate and molybdate electrolytes, respectively.

No abstract

Due to its unique properties, magnesium alloys at present are widely used in aircraft and defence technologies, despite the significant drawback as low corrosion resistance. The most effective method of alloys protection is micro-arc oxidation (MAO). But firstly, the alloys oxidation has a number of difficulties, and secondly, the ceramic coatings have an effect on thermal-physical characteristics of modified material. The presented report devotes of the developed technological mode of a protective coating forming on the ultralight alloy Mg-8Li-1Al-0.6Ce by the MAO method. The role of cathodic polarization at the treatment was mentioned. An integrated assessment of the ability to thermal conductivity and corrosion resistance of the modified alloy was made. Despite the relatively small thickness and the presence of pores, the resulting coating provides sufficiently high corrosion resistance; the formed coating slightly (not more than 5%) reduces the thermal conductivity of the ultralight Mg alloy.

The problem of studying the properties of coatings obtained by micro arc oxidation of a magnesium alloy in an alkaline electrolyte is considered.