Influence of the Sintering Operation on the Structure and Properties of Dispersion-Hardened Iron-Based Alloys

Purpose of research. To determine the dependence of the pre-sintering parameters on the formation of the structure and properties of high-density dispersed-hardened alloy alloys for further efficient use of heat treatment in order to improve their mechanical and operational properties.

Technological features in the formation of high-quality interparticle fusion of dispersed-hardened materials are considered. Qualitative splicing is primarily determined by the mechanical properties of the alloys, which show the degree of its completeness during sintering. Depending on the density of the materials, the sintering temperature and the percentage of carbon that is introduced into the alloy charge.

To achieve this goal, it was necessary to establish the regularities of the formation of properties and the creation of qualitative bonds between the particles of dispersed-hardened alloys when carbon was introduced into the charge. Methods. This paper provides a detailed description of the heat treatment of alloys and examines the change in structural features compared to compact materials. The test was carried out in a medium of dissociated ammonia at various temperatures. The obtained samples were subjected to mechanical tests.

Results. The following has been experimentally established – The strength and plastic characteristics of sintered alloys are determined from the density of the samples, as well as from the carbon introduced into the charge. According to the data of this work, it follows that sintering for 30 minutes for pure iron alloys is the minimum time at which carbon homogenization occurs in the metal matrix. The sintering temperature of 1100°C for such materials is absolutely reasonable and an increase in the sintering temperature will not matter to accelerate the sintering process.

Conclusions. The paper shows the strength properties of the alloys under consideration, depending on the percentage of carbon content in the initial charge. For the PL-N4D2M alloy, the optimal sintering temperature is 1200°C, which is 100°C higher than the sintering temperature for iron alloys.

1. Egorov M. S., Eremeeva Zh. V., Egorova E. V. Metody polucheniya zheleznykh i stal'nykh poroshkov i konstruktsionnykh materialov na ikh osnove [Methods for obtaining iron and steel powders and structural materials based on them]. Rostov-on-Don, Don St. Techn. Univ. Publ., 2021. 250 p.

2. Volkov G. M. Istoricheskie predposylki i perspektivy nanotekhnologii [Historical background and prospects of nanotechnology]. Nanotekhnologii: nauka i proizvodstvo = Nanotechnologies: science and production, 2017, no. 2, рр. 23–31.

3. Volkogon G. M., Gavrilin O. S., Ratner A. D. Proizvodstvo metallicheskikh nanoporoshkov khimicheskimi sposobami [Production of metal nanopowders by chemical methods]. Nanotekhnologii i informatsionnye tekhnologii – tekhnologii XXI veka = Nanotechnologies and information technologies - technologies of the XXI century. Moscow, MGOU Publ., 2006, рр. 127–129.

4. Egorov M. S., Egorov S. N. Goryachedeformirovannye poroshkovye nizkolegirovannye konstruktsionnye stali [Hot-wrought powder low-alloy structural steels]. Novocherkassk, Volgodonsk in-t (brangh) URGTU (NPI), 2008. 54 p.

5. Kablov E. N., Ospennikova O. G., Bazyleva O. A. Materialy dlya vysokoteplonagruzhennykh detalei gazoturbinnykh dvigatelei [Materials for highly heat-loaded parts of gas turbine engines]. Vestnik Moskovskogo gosudarstvennogo tekhnicheskogo universiteta im. N. E. Baumana. Seriya: Mashinostroenie = Bulletin of the Bauman Moscow State Technical University. Series: Mechanical Engineering, 2011, no. SP2, pp. 13–19.

6. Robert-Perron E., Blais C., Pelletier S. Tensile properties of sinter hardened powder metallurgy components machined in their green state. Powder Metallurgy, 2009, vol. 52, no. 1, рр. 80–83.

7. Kondo H., Hegedus M. Current trends and challenges in the global aviation industry. Acta Metall. Slovaca, 2020, vol. 26, рр. 141–143.

8. Chang I., Zhao Y. Automotive applications of powder metallurgy in advanced in powder metallurgy. Cambridge, UK. Woodhead Publishing Series, 2013, рр. 493–519.

9. Antsiferova V. N. Problemy sovremennykh materialov i tekhnologii [Problems of modern materials and technologies]. Perm, Perm St. Univ. Publ., 1995. 196 p.

10. Dorofeev V. Yu., Kochkarova Kh. S. [Hot stamping of high-chromium powder white cast iron microalloyed with calcium]. Poroshkovaya metallurgiya: inzheneriya poverkhnosti, novye poroshkovye kompozitsionnye materialy. Sbornik dokladov 10-go Mezhdunarodnogo simposiuma [Powder metallurgy: surface engineering, new powder composite materials. Welding. Sat. report 10th Intern. symp.]; ed. By A. F. Ilyushchenko, eds. Minsk, Belaruskaya Navuka Publ., 2017, рр. 93–104. (In Russ.)

11. Chagnon Fr. Effect of Ni addition route on static and dynamic properties of Fe-2Cu1.8Ni-0.5Mo-0.65C and Fe-2Cu-1.8Ni-0.5Mo-0.85C PM steels. Adv. Powder Metall. Part. Mater., 2012, vol. 2, рр. 10.73–10.84.

12. Antsiferov V. N., Perelman V. E. Mekhanika protsessov pressovaniya poroshkovykh i kompozitsionnykh materialov [Mechanics of the processes of pressing powder and composite materials]. Moscow, Graal Publ., 2001. 628 p.

13. Schade C., Murphy T., Lawley A., Doherty R. The influence of silicon on the mechanical properties and hardenability of PM steels. Advances in Powder Metallurgy and Particulate Materials – 2013. Proceedings of the 2013 International Conference on Powder Metallurgy and Particulate Materials, PowderMet. Chicago, Illions, 2013, рр. 754–772.

14. Eremeeva Zh. V., Nikitin N. M., Korobov N. P., Ter-Vaganyants Yu. S. Issledovanie protsessov termicheskoi obrabotki poroshkovykh stalei, legirovannykh nanorazmernymi dobavkami [Investigation of the processes of heat treatment of powder steels alloyed with nanosized additives]. Nanotekhnologii: nauka i proizvodstvo = Nanotechnologies: science and production, 2016, no. 1 (38), pp. 63–74.

15. Eremeeva Zh. V., Sharipzyanova G. Kh., Nikitin N. M. Poroshkovaya metallurgiya v avtomobilestroenii i drugikh otraslyakh promyshlennosti [Powder metallurgy in the automotive industry and other industries]. Moscow, Universitet Mashinostroeniya Publ., 2014. 276 p.

16. Gurevich Yu. G., Antsiferov V. N., Savinykh L. M., Oglezneva S. A., Bulanov V. Ya. Iznosostoikie kompozitsionnye materialy [Wear-resistant composite materials]. Yekaterinburg, UrO RAN, 2005. 215 p.

17. Skorikov R. A. Elektroimpul'snoe spekanie poroshkovoi uglerodistoi stali, uprochnennoi nanochastitsami [Electropulse sintering of carbon steel powder hardened with nanoparticles]. Nanotekhnologii: nauka i proizvodstvo = Nanotechnologies: science and production, 2015, no. 2 (34), pp. 34–40.

18. Dyachkova L. N., Dechko M. M. Vliyanie nanodispersnykh dobavok na strukturu i svoistva poroshkovoi uglerodistoi i vysokokhromistoi stali [Influence of nanodispersed additives on the structure and properties of powdered carbon and high-chromium steels]. Nanotekhnologii: nauka i proizvodstvo = Nanotechnologies: science and production, 2015, no. 3 (35), pp. 5–14.

19. Panov V. S., Skorikov R. A. Vliyanie nanorazmernykh legiruyushchikh dobavok na strukturu i svoistva poroshkovykh uglerodistykh stalei [Influence of nanosized alloying additives on the structure and properties of powdered carbon steels]. Nanotekhnologii: nauka i proizvodstvo = Nanotechnologies: science and production, 2015, no. 3 (35), pp. 40–45.

20. Egorov M. S., Egorova R. V. Plastichnost' kompozitsionnykh materialov s opredeleniem temperaturnykh rezhimov goryachei shtampovki, isklyuchayushchikh poyavlenie defektov v strukture materiala [Plasticity of composite materials with the determination of temperature regimes of hot stamping, excluding the appearance of defects in the structure of the material]. Zagotovitel'nye proizvodstva v mashinostroenii = Procurement production in mechanical engineering, 2019, vol. 17, no. 2, рр. 66–72.