Influence of Powder Charge Composition on the Structure and Properties of T15K6 Hard Alloy

The purpose of the study is to determine the effect of nanosized additives on the structure and properties of the T15K6 hard alloy.
Methods. These studies were carried out using an S-3400N electron microscope. The mechanical and physical properties of the structure of a hard alloy of the WC-TiC-Co system were studied using the example of T15K6 when nanosized tungsten powder and nanosized tungsten carbide powder with cobalt deposited on it were introduced into the initial charge using an optical and electron microscope; An X-ray spectrum analysis of the obtained samples of the T15K6 hard alloy was carried out on a DRON-4 X-ray diffractometer.
Results. A hard alloy of the WC-TiC-Co system was studied with the introduction of nanosized tungsten powder into the initial charge, as well as with the introduction of nanosized tungsten carbide with cobalt deposited on its surface.In the work, the used powders of tungsten, nano-tungsten, cobalt, titanium carbide, tungsten carbide, nano-powder of tungsten carbide were studied, and the microstructure of the obtained hard alloys was also studied. It is shown that the coercive force of the T15K6 alloy depends on the size of the cobalt phase regions in the alloy; measuring its value makes it possible to judge the size of carbide grains. To improve the strength properties of hard alloys of the WC-TiCCo system, it is recommended to introduce nanosized WC additives or WC nanopowder with deposited cobalt.
Conclusion. To improve the strength properties of hard alloys of the WC-TiC-Co system, it is recommended to introduce nanosized WC additives or WC nanopowder with deposited cobalt. The introduction of these additives into the composition of the powder charge of the T15K6 hard alloy leads to an increase in the ultimate bending strength by 15%. The introduction of nanosized WC additives or WC nanopowder with deposited cobalt makes it possible to obtain a fine-grained structure with a grain size of no more than 4–6 μm.

1. Fal'kovskiy V. A., Klyachko L. I. Tverdye splavy [Hard alloys]. Moscow, Ruda i metally Publ., 2005. 413 р.

2. Andrievskiy R. A., Ragulya A. V. Nanostrukturnye materialy [Nanostructured materials]. Moscow, AKADEMA Publ., 2005. 178 р.

3. Park Y. J., Hwang N. M., Yoon D. Y. Abnormal growth of faceted (WC) grains in a (Co) liquid matrix. Metallurgical and Materials Transactions A, 1996, vol. 27, is. 9, pp. 2809–2819.

4. Janisch D., Reichel B. B. [The way of tungsten carbide formation by gas phase corbonization]. Patent Germany, no. 198.52.459, 2000.

5. Mccandlish L. E., Kear B. H., Bhatia S. J. Mixing tungsten and cobalt compounds, drying to form homogeneous precursor powder, thermochemically converting in carburizing gas. Patent US, no. 5352269 A. 1994.

6. Kudrya N. A., Fal'kovskiy V. A., Chistyakova V. A. Vyyasneniye vozmozhnosti primeneniya plazmennogo poroshka vol'frama. Otchet No. 19-8211-38 [Finding out the possibility of using plasma tungsten powder. Report No. 19-8211-38]. Moscow, VNIITS Publ., 1983. 157 р.

7. Almond E. A., Lay L. A., Gee M. G. Сomparison of sliding and abrasive wear mechanisms in ceramics and cemented carbides. Science of Hard Materials, Proceedings of the International Conference. Rhodes, Greece, 1986, iss. 75, pp. 919–948.

8. Wirmark C., Dunlop G. L. Phase transformation in the binder phase of Co-W-C cemented carbides. Proc. Int. Conf. Sci. Hard Mater., eds.: R. K.Viswandham, D. Rouclihle and J. Gurland. Plenum, New York, 1983, pp. 311–327.

9. Petridis A. V., Tolkushev A. A., Ageev E. V. Sostav i svoystva poroshkov, poluchennykh iz otkhodov tverdykh splavov metodom elektroerozionnogo dispergirovaniya (EED) [Composition and properties of powders obtained from solid alloy waste by the method of electroerosive dispersion (EED)]. Tekhnologiya metallov = Technology of metals, 2005, no. 6, pp. 13–16.

10. Borovinskaya I. P., Ignat’eva T. I., Vershinnikov V. I., Sachkova N. V. Preparation of tungsten carbide nanopowders by self-propagating high temperature synthesis. Inorganic Materials, 2004, vol. 40, no. 10, pp. 1043–1048.

11. Ageev E. V. Izucheniye fiziko-mekhanicheskikh svoystv tverdosplavnykh poroshkov, poluchennykh elektroerozionnym dispergirovaniyem otkhodov [Study of physico-mechanical properties of carbide powders obtained by electroerosive dispersion of waste]. Uprochnyayushchiye tekhnologii i pokrytiya = Hardening technologies and coatings, 2011, no. 6 (78), pp. 8–14.

12. Ageev E. B., Gadalov V. N., Ageeva E. B., Bobryshev R. V. Poroshki, poluchennyye elektroerozionnym dispergirovaniyem otkhodov tverdykh splavov, perspektivnyy material dlya vosstanovleniya detaley avtotraktornoy tekhniki [Powders obtained by electroerosive dispersion of solid alloy waste, a promising material for the restoration of parts of automotive equipment]. Izvestiya Yugo-Zapadnogo gosudarstennogo universiteta = Proceedings of the Southwest State University. Series: Engineering and Technologies, 2012, no. 1, pp. 182–189.

13. Zaytsev A. A., Borovinskaya I. P., Vershinnikov V. I., Konyashin I., Patsera E. I., Levashov E. A., Ries B. Near-nano and coarse-grain WC powders obtained by the self-propagating high-temperature synthesis and cemented carbides on their basis. Part I. Structure, composition and properties of WC powders. Int. Journal of Refractory Metals and Hard Materials, 2015, no. 50, pp. 146–151.

14. Nie Hongbo, Zeng Qisen, Zheng Jianping, Wen Xiao, Yu Yang. The preparation, preparation mechanism and properties of extra coarse-grained WC – Co hardmetals. Metal Powder Report, 2017, vol. 72, is. 3, pp. 188–194.

15. Kim B. K, Ha G. G, Woo Y. Method of production WC/Co cemented carbide using grain growth inhibitor. Patent US, no. 6511551, 2003.

16. Kirklin S., Saal J. E., Hegde V. I., Wolverton C. High-throughput computational search for strengthening precipitations in alloys. Acta Materialia, 2016, vol. 102, pp. 125–135.

17. Kawakami M., Kitamura K. Segregation layers of grain growth inhibitors at WC/WC interfaces in VC-doped submicron-grained WC–Co cemented carbides. International Journal of Refractory Metals and Hard Materials, 2015, vol. 52, pp. 229–234.

18. Sun Lan, Xiong Ji, Guo Zhixing. Effects of nano-Al2O3 additions on microstructures and properties of WC-8Co hard metals. Advanced Materials Research. Zuerich, Switzerland, 2010, pp. 97–101.

19. Panov V. S., Chuvilin A. M., Fal'kovskiy V. A. Tekhnologiya i svoystva spechennykh tverdykh splavov [Technology and properties of sintered hard alloys]. Ed. 2th, revised and expanded. Moscow, MISiS Publ., 2004. 461 p.

20. Jia K., Fischer T. E. Abrasion resistance of nanostructured and conventional cemented carbides. Wear, 1996, vol. 200, pp. 206–214.

21. Fal'kovskiy V. S. Innovatsii v tekhnologii tverdykh splavov: nanoi ul'tradispersnye struktury [Innovations in Technology of hard alloys: nanoand ultra-dispersed structures]. Moscow, MITKHT Publ., 2008. 69 p.

22. Borovskiy G. V., Blagoveshchenskiy Yu. V., Abramov A. V., eds. Nanostrukturnyye tverdyye splavy WC–Co, proizvedennyye iz plazmokhimicheskikh poroshkov [Nanostructured WC–Co hard alloys produced from plasma chemical powders]. Trudy 17 Planzeye seminar = Proceedings of the 17th Plansee seminar, 2009, no. 2, pp. 224–229.

23. Panov V. S. Osnovnye napravleniya usovershenstvovaniya sostava i svoystv tverdykh splavov (analiticheskiy obzor) [The main directions of improving the composition and properties of solid alloys (analytical review)]. Materialovedeniye = Materials Science, 2020, no. 4, pp. 37– 41.

24. Sasai S., Santo A., Shimizu T., Kojima T., Itoh H. Development of recycling system of WC-Co cermet scraps]. Waste Management and the Environment. Ecology and the Enviroment, 2002, vol. 56, pp. 1322.

25. Panov V. S. Rol' svyazuyushchey fazy v tverdykh splavakh (analiticheskiy obzor) [The role of the binding phase in hard alloys (analytical review)]. Materialovedeniye = Material science, 2020, no. 3, pp. 35–38.

26. Mannesson K., Borgh I., eds. Abnormal grain growth in cemented carbides – Experiments and simulations. Int. J. Refract. Met. Hard Mater., 2011, vol. 29, pp. 488–494.

27. Panov V. S. Nanostructured sintered WC–Co hard metals (review) [Nanostructured sintered WC–Co hard metals (review)]. Powder Metallurgy and Metal Ceramics, 2015, vol. 53, no. 11, pp. 643–654.

28. Panov V. S. Subdispersnyye i nanorazmernyye tverdyye splavy WC – Co [Subdisperse and nanoscale hard alloys WC – CO]. Nanotekhnologii: nauka i proizvodstvo = Nanotechnologies: science and production, 2017, no. 3, pp. 3–18.

29. Panov V. S. Teoreticheskiye osnovy prochnosti spechennykh tverdykh splavov [Theoretical foundations of strength of sintered hard alloys]. Moscow, MISiS Publ., 2011. 82 p.

30. Zaytsev A. A., Vershinnikov V. I., Panov V. S., eds. Vliyanie tekhnologicheskikh parametrov spekaniya na strukturu i svoistva tverdogo splava VK5 iz SVS-poroshka karbida vol'frama [The influence of technological parameters of sintering on the structure and properties of a solid VK5 alloy made of SHS powder of tungsten carbide]. Izvestiya vuzov. Poroshkovaya metallurgiya i funktsional'nye pokrytiya = Proceedings of universities. Powder metallurgy and functional coatings, 2013, no. 3, pp. 21.

31. Kreymer G. S. Prochnost' tverdykh splavov [Strength of hard alloys]. 2th ed. Moscow, Metallurgiya Publ., 1971. 247 p.