SEM, 2020, #1, 46-51 pages
Influence of crystallization rate on the microstruсture and properties of Ti–TiB alloy
D.O. Remisov, Yu.I. Bogomol, P.I. Loboda
NTUU «Igor Sikorsky Kyiv Polytechnic Institute». 37 Pobedy Ave., 03056, Kyiv, Ukraine. E-mail: firstname.lastname@example.org
Kinetics of the process of directional crystallization of a eutectic alloy of Ti–TiB system under the conditions of
cruciblelss zone melting of powder compacts was studied. It is proved that increase of the alloy crystallization rate
from 1 up to 4 mm/min leads to 2.0...2.5 times increase of the number of TiB inclusions, elongated predominantly
in the direction of crystallization, that agrees well with the impact of diffusion mass transfer in the melt ahead of
the crystallization front. Increase of temperature gradient in the eutectic alloy crystal leads to approximately two
times reduction of the dimensions and increase of the number of inclusions by 40 and more times. Hardness value,
measured by Vickers method at more than 3 N loads on the indenter, can be an integral characteristic of the properties
of directionally crystallized alloy. Ref. 6, Tabl. 2, Fig. 9.
Keywords: crystal; crucibleless zone melting; titanium; alloy; structure; diboride; titanium alloy
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