2020 №01 (05) DOI of Article
2020 №01 (01)

Electrometallurgy Today 2020 #01
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: decan@iff.kpi.ua

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

Received 18.02.2020


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