Berezos V. Elaboration of equipment and technology of large in diameter hollow ingots of titanium alloys via electron beam melting methods.

The thesis is devoted to scientific elaboration of equipment and technology as well as elaboration of prospective processes of manufacturing of the new class titanium alloys semimanufactures - large in diameter hollow ingots that can be further used for large dimension tubes manufacturing. The thesis presents optimal conditions for crystallization of hollow ingots - titanium alloy Ti-6Al-4V ?600/200 mm. The dependence of effectiveness of hydrogen refining and of aluminium evaporation on productivity of hollow ingot melting via electron beam melting is established. Optimal technological regimes of manufacturing of large in diameter hollow titanium alloy ingot via electron beam melting are elaborated. For the first time in the world the elaborated technology is used to get a large dimension hollow ingot – mass 2000 kg, titanium alloy VT6 (Ti-6Al-4V) – via electron beam melting with a cold hearth.