Obrabotka Metallov. 2017 no. 2(75)

ОБРАБОТКА МЕТАЛЛОВ № 2 (75) 2017 53 МАТЕРИАЛОВЕДЕНИЕ 16. Miller W.S., Humphreys F.J. Strengthening mechanisms in particulate metal matrix composites // Scripta Metallurgica & Materialia. – 1991. – Vol. 25, iss. 1. – P. 33–38. – doi: http://dx.doi.org/10.1016/0956- 716X(91)90349-6. 17. Karczewski K., Stępniowski W.J., Jóźwiak S. Highly-porous FeAl intermetallic foams formed via sin- tering with Eosin Y as a gas releasing agent // Materials Letters. – 2016. – Vol. 178. – P. 268–271. – doi: http:// dx.doi.org/10.1016/j.matlet.2016.05.047. OBRABOTKAMETALLOV (METAL WORKING AND MATERIAL SCIENCE) N 2 (75), April – June 2017, Pages 45–54 Spark Plasma Sintering of the mixtures of metallic powders and metal matrix composites: Peculiarities of the structure formation and properties of the sintered materials Dudina D. V. 1, 2, 3 , Ph.D. (Engineering), Senior Researcher, e-mail: dina1807@gmail.com 1 Lavrentyev Institute of Hydrodynamics of the Siberian Branch of the RAS, 15 Ac. Lavrentieva ave., Novosibirsk, 630090, Russian Federation 2 Novosibirsk State Technical University, 20 Prospect K. Marksa, Novosibirsk, 630073, Russian Federation 3 Institute of Solid State Chemistry and Mechanochemistry Siberian Branch of Russian Academy of Sciences, 18 Kutateladze st., Novosibirsk, 630128, Russian Federation Abstract The peculiarities of the behavior of the powder mixtures of metals and metal matrix composites during Spark Plasma Sintering (SPS) using Ti 3 SiC 2 -Cu, Fe-Ag, NiO-Ni, Cu 2 O-Cu, and Fe-Al systems as examples are analyzed in the work. The physical and chemical aspects of the formation of contacts between composite agglomerates obtained by mechanical treatment of the powder mixtures in a high-energy ball mill and the possibilities of the SPS method for the production of metal matrix composites combining different strengthening mechanisms are discussed. In the Ti 3 SiC 2 -Cu composites obtained by mechanical milling and SPS, the copper matrix remains in the nanocrystalline state, and the total contribution of dislocation and grain boundary strengthening is greater than the contribution of dispersion strengthening. Microstructural studies of the sintered Ti 3 SiC 2 -Cu and Fe-Ag compacts show that during SPS of mechanically milled powders, areas of inter-agglomerate contacts can experience melting. In the systems capable of interfacial interactions, the latter preferentially occur at the inter-agglomerate contacts. The conditions for the efficient reduction of oxide films present on the surface of metallic particles during the SPS using a partially oxidized copper powder containing Cu 2 O and a partially oxidized nickel powder containing NiO are examined. It is found that under the SPS conditions commonly used in the consolidation practice of metallic powders, elimination of oxide films present on the surface of metallic powders is due to chemical reduction of the oxides by carbon. It is experimentally shown, that reactive pressureless SPS can produce porous materials of high open porosity. Keywords spark plasma sintering, metal matrix composites, metals, microstructure. DOI: 10.17212/1994-6309-2017-2-45–54 References 1. Groza J.R., Zavaliangos A. Nanostructured bulk solids by field activated sintering. Reviews on Advanced Materials Science , 2003, vol. 5, pp. 24–33. 2. Munir Z.A., Anselmi-Tamburini U., Ohyanagi M. The effect of electric field and pressure on the synthesis and consolidation of materials: a review of the spark plasma sintering method. Journal of Materials Science , 2006, vol. 41, iss. 3, pp. 763–777. doi: 10.1007/s10853-006-6555-2. 3. Orrù R., Licheri R., Locci A.M., Cincotti A., Cao G.C. Consolidation/synthesis of materials by electric current activated/assisted sintering. Materials Science and Engineering: R: Reports , 2009, vol. 63, iss. 4–6, pp. 127–287. doi: 10.1016/j.mser.2008.09.003.