Structure and phase states modification of AL-11SI-2CU alloy processed by ion-plasma jet and pulsed electron beam

• Published in: Surface & coatings technology 2020-02, Vol.383, p.125246, Article 125246
• Main Authors: Zaguliaev, D., Gromov, V., Rubannikova, Yu, Konovalov, S., Ivanov, Yu, Romanov, D., Semin, A.
• Format: Article
• Language: English
• Subjects: Alloying effects; Aluminum compounds; Casting alloys; Copper; Electron beams; Flux density; Inclusions; Iron; Nickel; Oxygen enrichment; Phase composition; Plasma jets; Processing with ion-plasma jet; Silicon; Spectrum analysis; Substructures; Surface layers; Titanium; Transmission electron diffraction; X ray spectra; Yttrium; Yttrium oxide
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2019.125246

In the research the investigations into structure, elemental and phase composition, defect substructure of Al-11Si-2Cu hypoeutectic alloy subjected to processing with ion-plasma jet consisting of titanium and yttrium oxide with subsequent irradiation by high intensity pulsed electron beam with energy density of beam of 25 J/cm2 (two-stage processing) were carried out by methods of scanning and transmission electron diffraction microscopy, micro-X-ray spectral analysis. It has been found that structure of Al-11Si-2Cu alloy in cast state demonstrates a polyphase morphologically varied character of the material. Microcraters, solid aluminium-based compounds, intermetallide and eutectic compounds are present in it. It has been revealed that two-stage processing of Al-11Si-2Cu alloy results in cardinal transformation of samples' surface layer structure and it is manifested in dissolution of silicon inclusions and intermetallides of micron and submicro dimensions typical of Al-11Si-2Cu cast alloy. It has been detected that ion-plasma jet effect on alloy surface is accompanied by both alloying of surface layer by plasma elements and penetration of initial powder particles of yttrium oxide. Along with atoms of initial material (Al, Si, Cu, Ni, Fe) the surface layer is enriched by atoms of titanium, yttrium, oxygen. It has been shown that a multielemental polyphase layer ≈60–70 μm thick having a submicro-nanocrystalline structure is formed as a result of two-stage processing. •The strengthening of hypoeutectic Al-11Si-2Cu alloy surface was performed by two-stage processing.•The effect of ion-plasma jet on the microstructure Al–11Si-2Cu alloy has been established.•The formation of polyphase submicro – nanodimensional states was revealed.