“Technology and research of materials” Chair, St. Petersburg State Polytechnic University (St. Petersburg, Russia):

Tsemenko V. N., Dr. Eng., Prof., Head of the Chair
Girshov V. L., Dr. Eng., Prof.

Central Scientific and Research Institute of Materials (St. Petersburg, Russia):

Mazurov S. A., Cand. Eng., Sr. Scientific fellow

E-mail (common): plast-ftim@mail.ru

Technology for high-speed steel production development by means of powder metallurgy opens new ways to improve operating properties. Technology of hot extrusion of high-speed steels in hermetic capsules has an advantage compare to technology of hot gas-static pressing. Hot extrusion in hermetic capsules allows us to use more high-production equipment such as hydraulic presses. The main disadvantage of hot extrusion in hermetic capsules is low productivity after capsules removing. Technological parameters of powder material in steel capsule extrusion are determined in present research by means of numerical simulation. Determined parameters allow to increase process productivity. Combination of extrusion and subsequent plastic deformation leads to improvement of mechanical properties of rods of high-speed steels compare to traditional technologies. It is shown that improvement of mechanical properties is reached according to more uniform distribution of alloying elements in final products compare to traditional technologies. This statement leads to more uniform distribution of fi ne carbides in microstructure and, as a result of it, fine austenite grain size is formed after quenching. At the same time it is not necessary to use high amounts of deformation during extrusion of billets in hermetic capsules.

1. Girshov V. L. Voprosy materialovedeniya — Inorganic Materials: Applied Research. 2008. No. 2. pp. 33–42.
2. Kovalchenko M. S. Izvestiya vuzov. Poroshkovaya metallurgiya — Proceedings of Universities. Powder metallurgy. 2009. No. 3/4. pp. 13–26.
3. Rudskoy A. I., Rybin Yu. I., Tsemenko V. N. Teoriya i modelirovanie protsessov deformirovaniya poroshkovykh i poristykh materialov (Theory and modeling of processes of deformation of powder and porous materials). Saint Petersburg : Nauka, 2012. 416 p.
4. Abramov A. A., Girshov V. L., Mazurov S. A., Samoylenko L. S. Kapsula dlya izgotovleniya izdeliy iz metallicheskikh poroshkov (Capsule for manufacturing of products from metallic powders). Patent RF, No. 81111. Applied: October 10, 2008. Published: March 10, 2009.
5. Girshov V. L. Metalloobrabotka — Metal processing. 2001. No. 4. pp. 40–41.