2018 №04 (02) DOI of Article
2018 №04 (04)

Electrometallurgy Today 2018 #04
SEM, 2018, #4, 42-51 pages
Structure of large profiled single crystals of tungsten, produced by additive plasma-induction surfacing

Journal                    Sovremennaya Elektrometallurgiya
Publisher                 International Association «Welding»
ISSN                      2415-8445 (print)
Issue                       № 4, 2018 (November)
Pages                      42-51
B. E. Paton, G. M. Grigorenko, L. I. Markashova, V. A. Shapovalov, E. N. Berdnikova, E. V. Polovetsky, V. V., Yakusha, A.N. Gnizdylo
E.O. Paton Electric Welding Institute of the NAS of Ukraine. 11 Kazimir Malevich Str., 03150, Kyiv, Ukraine. E-mail: office@paton.kiev.ua

Studied was the structure of large tungsten billet, produced by the method of additive plasma-induction layer-by-layer growing on monocrystalline primer at different speeds of the process (17…70 mm/min) The investigations ( of microhardness, sizes of subgrained structure, angles of subgraines disorientation, nature of distribution of dislocations, etc.) were carried out at all the structural levels by using a complex of experimental methods of modern physical materials science, including light, scanning and transmission microdiffraction electron microscopy. It is shown that the ingot represents a monocrystalline body with a crystallographic orientation, preset by the priming crystal, The increase in rate of growing up to 70 mm/min leads to a negligible decrease in microhardness, refining of structure at the uniform distribution of density of dislocations that allows producing tungsten single crystals with a perfect monocrystalline structure (with low-angle boundaries) at angles of disorientation, not exceeding 3о. Ref. 12, Tabl. 3, Fig. 7.
Key words: tungsten; plasma-induction growing; single-crystal ingot; structure; disorientation of subgrains; density of dislocations
Received:                30.08.18
Published:               15.11.18

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