Multilayer structure of Al-Si alloy after electro-explosion alloying with yttrium oxide powder

Electro-explosion alloying of a eutectic Al-Si alloy (silumin) with yttrium oxide powder is carried out to form a coating on the material surface with advanced characteristics. Transmission microscopy of thin foils and x-ray micro-spectral analysis are performed to identify the elemental and phase composition and the defect substructure of the coating. The study reveals a four-layer structure comprising a surface layer (1), interlayers (2 and 3), and an interjacent (4) layer, with thicknesses ranging from 100 to 900 nm, as well as a multi-phase nanocrystal structure consisting mostly of aluminium and yttrium oxides and silicates. It is established that the coating is a multi-element alloy, and that its main components are oxygen, aluminium, yttrium, silicon and titanium (oxygen and yttrium atoms are located in layers 1, 2 and 4, aluminium atoms in layer 3, and silicon and titanium atoms in layers 1–3).