Electrometallurgy Today, 2018, №04



2018 №04 (02)

DOI of Article 10.15407/sem2018.04.03

2018 №04 (04)

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Electrometallurgy Today (Sovremennaya Elektrometallurgiya), 2018, #4, 42-51 pages
 

Structure of large profiled single crystals of tungsten, produced by additive plasma-induction surfacing

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 3^о. 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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