Orenburg State University, Department of Materials Science and Engineering, Orenburg, Russia

V. I. Yurshev, Head of the Department, Candidate of Technical Sciences, Associate Professor, e-mail: yvi170858@rambler.ru
A. S. Kirilenko, Senior Lecturer, Candidate of Technical Sciences, e-mail: as@askirilenko.ru
I. V. Yurshev, Head of the Laboratory, e-mail: chat_ilya@mail.ru

Orenburg State University, Engineering Center, Orenburg, Russia

S. V. Boyko, Director, Candidate of Technical Sciences, Associate Professor, e-mail: boikosv61@mail.ru

The article presents the results of a study on pressing and sintering of cemented carbide plates in order to increase the durability of metal-cutting tools. The substantiation and optimization of the cemented carbide mixture pressing conditions is shown. Various plasticizers were used in the preparation of the mixture. Pressing modes and results on pressing force and elastic aftereffect coefficient are given. After sintering the samples, the microstructure, porosity, density, and hardness are determined. Microstructures are shown with the use of plasticizers SKD II (BR-1203) and PEG-1500. According to the granulometric composition, the initial mixture had an average particle size of 0.7601 microns. The pressing was carried out with preliminary vibration-mechanical treatment of a mold filled with a cemented carbide mixture with a plasticizer. The dependences of the density and the coefficient of elastic aftereffect on the pressing pressure are obtained. The variation ranges of pressing speed and pressure were as follows: pressing speed — from 3 to 15 kN/s, pressing pressure — from 100 to 900 MPa. Prov iding pressing speeds in the required pressure range was carried out on presses with loads up to 100 kN and up to 1250 kN. It has been established that polyethylene glycolbased plasticizers are preferable in terms of elastic aftereffect, density and porosity. When optimizing the parameters of pressing the VK10-HOM mixture in the selected intervals of varying factors, a plan for a complete two-factor threelevel experiment for each type of plasticizer was drawn up. The density of compressed samples and the coefficient of elastic aftereffect were chosen as the optimization criteria. In the joint analysis of experimental response surfaces, a compromise task to determine the optimal parameters of the pressing process was solved for optimization criteria. The microstructure of plates obtained under the optimal pressing mode, using PEG-1500 plasticizer at sintering temperature of 1390 °C, shows low porosity, absence of undesirable η-phase at higher values of density and hardness.
The study was conducted as part of the “Priority 2030” Strategic Academic Leadership Program.

1. Patrushev A. Yu., Farafonov D. P., Serov M. M. Tungsten-Free Hard Alloys: Manufacturing Methods, Structure And Properties (Review). Proceedings of VIAM. 2021. Vol. 105, Iss. 11. pp. 66–81.
2. Sharipzyanova G. Kh., Eremeeva Zh. V. Research of Production Technology Carbide Materials. Izvestiya Tula State University. Nauki o Zemle. 2023. No. 1. pp. 360–370.
3. Bozorov A., Kayumov B., Asadova M. Modification of Card Alloy VK-6 and VK-8 for the Purpose Increasing Wear Resistance by Alloying with Rhenium. Universum: Technical Sciences. 2023. Vol. 115, Iss. 10. DOI: 10.32743/UniTech.2023.115.10.16131
4 Wu Y., Lu Z., Qin Y., Bao Z., Luo L. Ultrafine/Nano WC-Co Cemented Carbide: Overview of Preparation and Key Technologies. Journal of Materials Research and Technology. 2023. Vol. 27. pp. 5822–5839.
5. García J., Strelsky W. Process Development and Scale Up of Cemented Carbide Production. In: Scale-up in Metallurgy. ProcessEng Engineering GmbH, 2010. pp. 235–266.
6. Ruys A. J. Cemented Carbides and Cermets. In: Metal-Reinforced Ceramics. Woodhead Publishing, 2021. pp. 285–325.
7. Zhdanovich G. M. Theory of Pressing Metal Powders. Moscow: Izdatelstvo “Metallurgy”, 1969. 264 p.
8. Handbook of Powder Technology. Vol. 11: Granulation. Eds. by Salman A. D., Hounslow M. J., Seville J. P. K. Oxford: Elsevier, 2006. 1402 p.
9. Staf H. Mechanical Modelling of Powder Compaction: Mechanical Modelling of Powder Compaction: Doctoral Thesis in Solid Mechanics. Sweden, 2020. 20 p.
10. Levashov E. A., Panov V. S., Konyashin I. Yu. History of Domestic Cemented Carbides. Izvestiya Vuzov. Poroshkovaya Metallurgiya i Funktsional’nye Pokrytiya. 2017. Iss. 3. pp. 14–21.
11. Trofimenko N. N., Efimochkin I. Yu., Dvoretskov R. M., Batienkov R. V. Obtaining Fine-Grained Cemented Carbide Alloys of the WC–Co System (Review). Proceedings of VIAM. 2020. Vol. 85, Iss. 1. pp. 92–100.
12 García J., Ciprés V. C., Blomqvist A., Kaplan B. Cemented Carbide Microstructures: Review. International Journal of Refractory Metals and Hard Materials. 2019. Vol. 80, pp. 40–68.
13. Panov V. S., Chuvilin A. M. Technology and Properties of Sintered Hard Alloys and Products Made from Them. Moscow: MISiS, 2001. 428 p.
14. Falkovsky V. A., Klyachko L. I. Hard Alloys. Moscow: Izdatelskiy dom “Ruda i Metally”, 2005. 418 p.
15. Girshov V. L., Kotov S. A., Tsemenko V. N. Modern Technologies in Powder Metallurgy. St. Petersburg: Izdatelstvo Politekhnicheskogo Universiteta, 2010. 385 p.
16. Tang X., Wang Z. Huang L. Wang X., Chang T., Huang P., Zhu Z. Preparation, Properties and Microstructure of High Hardness WC –Co Cemented Carbide Tool Materials for Ultra-Precision Machining. International Journal of Refractory Metals and Hard Materials. 2023. Vol. 116. 106356.
17. Kresse T., Meinhard D., Bernthaler T., Schneider G. Hardness of WC-Co Hard Metals: Preparation, Quantitative Microstructure Analysis, Structure-Property Relationship and Modelling. International Journal of Refractory Metals and Hard Materials. 2018. Vol. 75. pp. 287–293.
18. Rumman R., Chuan L. C., Quinton J. S., Ghomashchi R. Mechanical Properties and Microstructural Behaviour
of Microwave Sintered WC – Co. Metals and Materials International. 2020. Vol. 26. pp. 844–853.
19. Staf H., Nyrot E. F., Larsson P. L. On The Usage of a Neutron Source to Determine the Density Distribution in
Compacted Cemented Carbide Powder Compounds. Powder Metallurgy. 2018. Vol. 65, Iss. 5. pp. 389–394.

20. Staf H., Olsson E., Lindskog P., Larsson P.-L. On Rate-Dependence of Hardmetal Powder Pressing of Cutting Inserts. Powder Metallurgy. 2017. Vol. 60, Iss. 1. pp. 7–14.
21. Staf H., Olsson E., Lindskog P., Larsson P.-L. Determination of the Frictional Behavior at Compaction of Powder Materials Consisting of Spray-Dried Granules. Journal of Materials Engineering and Performance. 2018. Vol. 27. pp. 1308– 1317.
22. Kumar D. R., Kumar R. K., Philip P. K. Simulation of Dynamic Compaction of Metal Powders. Journal of Applied Physics. 1999. Vol. 85. pp. 767–775.
23. Olsson E., Larsson P. L. A Numerical Analysis of Cold Powder Compaction Based on Micromechanical Experiments. Powder Technology. 2013. Vol. 243. pp. 71–78.
24. Avdeenko E. N., Zamulaeva E. I., Zaitsev A. A., Konyashin I. Yu., Levashov E. A. Structure and Properties of Coarse-Grained WC-Со Hard Metals with Extra Homogeneous Microstructure. Izvestiya. Non-Ferrous Metallurgy. 2019. Iss. 4. pp. 70–78.
25. Straumal B. B., Konyashin I. Faceting/Roughening of WC/Binder Interfaces in Cemented Carbides: a Review. Materials. 2023. Vol. 16, Iss. 10. 3696.
26. Straumal B. B., Shchur L. N., Kagramanya D. G., Konstantinova E. P., Druzhinin A. V., Nekrasov A. N. Topology of WC/Co Interfaces in Cemented Carbides. Materials. 2023. Vol. 16, Iss. 16. 5560.
27. Peng Y., Wang H., Zhao C, Hu H., Liu X., Song X. Nanocrystalline WC–Co Composite with Ultrahigh Hardness and Toughness. Composites Part B: Engineering. 2020. Vol. 197. 108161.
28. Salmi K., Könberg E., Staf H., Larsson P.-L. Correlation Between Granule Strength and Green Strength at Compaction of Cemented Carbide Powder Materials. Journal of Materials Engineering and Performance. 2021. Vol. 30, Iss. 12. pp. 9078–9083.
29. GOST 20899–98 (ISO 4490–78). Metallic Powders. Determination of Flowability by Means of a Calibrated Funnel (Hall Flowmeter). Introduced: 01.07.2001.
30. GOST 19440-94. Metallic powders. Determination of Apparent Density. Part 1. Funnel Method. Part 2. Scott Volumeter Method. Introduced: 01.01.1997.
31. GOST 23402-78. Metal Powders. Microscopic Method of Particle Size Determination. Introduced: 01.01.1980.
32. Panov V. S. Main Directions of Improvement of Composition and Properties of Hard Alloys (Analytical Review). Materialovedenie. 2020. Iss. 4. pp. 37–41.
33. Pat. RU No. 2275274 С1. Int. Cl. B22F 3/02, B22F 3/03, B30B 15/02. Powder Material Pressing Method And Apparatus For Performing The Same. Zvonetskij V. I., Lopatin V. J., Morokov V. I., Shumenko V. V., Shumenko V. N. Appl. 18.11.2004, Publ. 27.04.2006, Bull. No. 12.
34. Fyodorov D. V., Semyonov O. V., Rumyantsev V. I., Ordanyan S. S. Influence Kind of Binder on the Properties of and Quality of Green Part from Hard Alloy BH8. Powder Metallurgy аnd Functional Coatings. 2014. Iss. 4. pp. 3–8.
35. Serdyuchenko K. Yu. Formation of Properties and Structure of Hard Alloys with Various Plasticizers: Abstract of Diss. ... Candidate of Technical Sciences. Moscow, 2006. 24 p.
36. Zakharov D. A. Improving the Composition, Structure, Technology and Application of Hard Alloys in the Production of Drill Bits: Diss. ... Candidate of Technical Sciences. Samara, 2014. 203 p.
37. GOST 14924-2019. Synthetic Cis-Butadiene Rubbers. Specifications. Introduced: 01.11.2021.
38. GOST 25280-90 (ST COMECON 6741–89, ISO 3927–77). Metal Powders. Method for Determination of Compressibility. Introduced: 01.07.1991.
39. ISO 3369:2006 (E). Impermeable Sintered Metal Materials and Hardmetals – Determination of density. Publ. (2^nd Ed.): 15.11.2006.
40. Grachev Yu. P., Plaksin Yu. M. Mathematical Methods of Experiment Planning. Moscow: DeLi print, 2005. 296 p.