The influence of homogeneous electrolyte composition on microplasma synthesis and characteristics of Fe-containing coatings on A1050 alloy

•Alkaline homogeneous electrolyte with Fe-EDTA complexes.•Dependencies of coating composition and thickness on electrolyte composition.•Passivating effect of sodium metasilicate. In this study the influence of the iron complexes and sodium metasilicate concentrations on the microstructure, thickness and total iron content in the microplasma coatings are reported. The microplasma synthesis of iron containing coatings on A1050 aluminum alloy at the alternative current is able to be controlled by the electrolyte composition variation. The coatings were obtained in electrolytes within the range of concentrations 0–0.05M for sodium metasilicate and 0.01–0.04M for iron EDTA complexes. The synthesis process was studied by the analysis of the anodic and cathodic voltage–time curves behavior, chemical composition of the coatings, their thickness and phase composition.