Funct. Mater. 2018; 25 (2): 267-273.

doi:https://doi.org/10.15407/fm25.02.267

Structure and properties of solid BK6-OM alloy after electrosintering

N.M.Prokopiv1, E.S.Gevorkyan2, R.V.Vovk3, O.V.Harchenko1, V.A.Chishkala3

1V.Bakul Institute for Superhard Materials, 2 Avtozavodskaya Str., 04074 Kyiv, Ukraine 2Ukrainian State University of Railway Transport, 7 Feierbakh Sq., 61050 Kharkiv, Ukraine 3V.Karazin Kharkiv National University, 4 Svobody Sq., 61022 Kharkiv, Ukraine

Abstract: 

In the paper we describe the results of the structure formation and physicomechanical properties of WC-Co hard alloy from he standard especially fine-grained BK6-OM mixture of KZTS (Russia) in electrosintering (ES) process with the use of a constant electric current (I = 3000 A) in a graphite mold in vacuum under pressure of 40 MPa and temperatures above (1320°C) and below (1220°C) of the solidus line of phase diagram. For comparison, samples from this mixture are sintered according to the standard technology in vacuum. The advantage of ES in conditions of the solid phase interaction (1200°C) is shown for obtaining the two-phase structure of hard alloy with high-density, without signs of recrystallization of carbide grains, from the standard mixture of BK6-OM, which increases by 30 % the thermal conductivity, hardness, and fracture toughness compared to the Sun. The mechanism of destruction of the samples after ES in conditions of impact loading is established.

Keywords: 
hard alloy, electrosintering, tungsten carbide, mechanical properties, vacuum sintering.
References: 

1. W.D.Schubert, Ultrafine and Nanograinedhardmetals: State of the Art - Their Properties and Application, Institut Sverhtverdyh Materialov, Kiev (2008).

2. M.Kramer, V.Kodash, E.Gevorkyan, Intern. Patent WO 2005/023729 A1.

3. V.S.Panov, A.M.Chuvilin, V.A.Falkovskiy, Technology and Properties of Sintered Hard Alloys and Products Made from them, MISiS, Moscow (2004) [in Russian].

4. V.A.Falkovskiy, L.I.Klyachko, Solid Alloys, Izdatelskiy Dom Rudaimetally, Moscow (2005) [in Russian].

5. V.I.Tretyakov, Basics of Metal Science and Technology of Production of Sintered Hard Alloys, Metallurgiya, Moscow (1976) [in Russian].

6. V.P.Bondarenko, E.G.Pavlotskaya, Sintering of Tungsten Hard Alloys in a Precisely Controlled Gas Environment, Naukova Dumka, Kiev (1995).

7. N.M.Prokopiv, V.P.Bondarenko, O.V.Harchenko, I.A.Gnatenko, Sverhtv. Mat., 47, 6 (2006).

8. H.Chen, D.Zwang, Y.Li, J. Chen, Proc. 15 Intern. Plansee Seminar, 180, 2 (2001).

9. USA Patent 6228139 (2001).

10. M.M.Prokopiv, O.V.Harchenko, Vesn. NTU HPI, 149, 57 (2013).

11. Ukraine Patent for Invention No. 90830.

12. A.V.Laptev, Porosh. Metal., 8, 3 (2001).

13. M.S.Kovalchenko, Porosh. Metal., 98, 1 (2001).

14. A.V.Ragulya, V.V.Skorohod, Consolidated Nanostructured Materials, Naukova Dumka, Kiev (2007) [in Russian].

15. R.Orru, R.Licheri, A.M.Locci et al., Mater. Sci. Eng., 127, 63 (2009)

16. Ukraine Patent No.72841 (2012).

17. E.S.Gevorkyan, L.A.Timofeeva, V.A.Chishkala, P.S.Kislyiy, Nanostrukt. Mat., 46, 2 (2006).

18. E.Gevorkyan, Y.Gutsalenko, N.Prokopiv, Durab.-Fiab., 1, 7 (2011).

19. Basics of EBSD http:// www.ebsd.com/ index.htm.

20. Yu.I.Azima, Yu.I.Belyaev, M.V.Kulakov, Prib. i Teh. Eksp., 248, 4 (1985).

21. USA Patent 6,617,271 (2003).

22. E.Sgourou, Y.Panayiotatos, R.V.Vovk, A.Chroneos, Appl. Sci., 674 (2017), doi:10.3390/app7070674. https://doi.org/10.3390/app7070674

23. O.V.Dobrovolskiy, M.Huth, V.A. Shklovskij, R.V.Vovk, Sci. Rep., 7:13740, doi:10.1038/s41598-017-14232-z. https://doi.org/10.1038/s41598-017-14232-z

24. O.V.Dobrovolskiy, V.V.Sosedkin, R.Sachser et al., J. Supercond Nov. Magn., 30, 735 (2017), doi:10.1007/s10948-016-3642-8. https://doi.org/10.1007/s10948-016-3642-8

25. A.L.Solovyov, L.V.Omelchenko, V.B.Stepanov et al., Phys. Rev. B, 94, 224505 (2016). https://doi.org/10.1103/PhysRevB.94.224505

26. M.A.Hadi, M.Roknuzzaman, A.Chroneos et al.,Comput. Mater. Sci., 137, 318 (2017). https://doi.org/10.1016/j.commatsci.2017.06.007

27. M.A.Hadi, R.V.Vovk, A.Chroneos, Journal of Materials Science: Mater. in Electron., 27, 11925 (2016), doi:10.1007/s10854-016-5338-z. https://doi.org/10.1007/s10854-016-5338-z

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