Structural Changes in the Surface of AK5M2 Alloy under the Influence of an Intense Pulsed Electron Beam

• Published in: Surface investigation, x-ray, synchrotron and neutron techniques Vol. 15; no. 1; pp. 183 - 189
• Main Authors: Konovalov, S. V., Ivanov, Yu. F., Zaguliaev, D. V., Yakupov, D. F., Ustinov, A. M., Kosinov, D. A.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 2021; Springer Nature B.V
• Subjects: Alloying elements; Aluminum base alloys; Cellular structure; Chemistry and Materials Science; Crystallization; Electron beams; Electron energy; Flux density; Materials Science; Microhardness; Phase composition; Pulse duration; Pulse repetition rate; Silicon; Solid solutions; Surface layers; Surfaces and Interfaces; Thin Films; silumin; electron-beam p; crystal-lattice parameter; microhardness; AK5M2 alloy; surface layer modification; structure; Al–Si alloy
• ISSN: 1027-4510; 1819-7094
• DOI: 10.1134/S1027451021010262

The surface of AK5M2 (Al–Si) alloy is treated with an intense pulsed electron beam in various modes (accelerated electron energy of 17 keV, electron-beam energy density of 10, 20, 30, 40 and 50 J/cm 2 , pulse duration of 50 and 200 μs, the number of pulses 3, and the pulse repetition rate 0.3 s –1 ). Microhardness analysis is performed, and the elemental and phase composition and state of the defect substructure of the surface layer are studied by scanning electron microscopy and X-ray phase analysis. It is shown that the increase in microhardness of the Al-Si alloy is due to the formation of a submicrometer-sized structure of high-speed cellular crystallization, the enrichment of an aluminum-based solid solution with alloying and impurity elements, and the reprecipitation of nanoscale particles of strengthening phases. It is suggested that the higher values of the microhardness found in the alloy irradiated at 50 J/cm 2 and 50 μs compared with the alloy irradiated at 50 J/cm 2 and 200 μs are due to the process of tempering the material, which have a greater development with a longer duration of exposure to beam electrons per pulse.