Field Assisted Sintering Technique Compaction of Ultrafine-Grained Binderless WC Hard Metals

• Authors: M. Dopita , A. Salomon , D. Chmelik , B. Reichelt , D. Rafaja
• Languages of publication: EN

Abstracts

EN

Tungsten carbide (WC) powder having a crystallite size around 55 nm and the Brunauer-Emmett-Teller specific surface area 2.75 m^2/g was sintered using the field assisted sintering/spark plasma sintering technique. Sintered samples were investigated using different analytical methods providing detailed information on the microstructure and mechanical properties of materials. Density and porosity of specimens were determined using the Archimedes principle and optical and scanning electron micrographs. The X-ray diffraction investigations provided the information on the crystal real structure and crystallite sizes. The electron backscatter diffraction measurements yielded the details about the grain size, frequency, and distributions of grain boundaries. Finally, the essential mechanical properties of sintered samples were obtained from the hardness and fracture toughness measurements. The influences of individual sintering conditions: sintering temperature and sintering time especially, on the microstructure and mechanical properties of sintered specimens were derived. Fully compact samples having the Vickers hardness HV10 around 29 GPa and fracture toughness K_{Ic} approximately 7.2 MPa m^{1/2} were sintered from temperatures of 1800C and holding times 1 min. Specimens sintered at lower temperatures showed lower density which resulted in a significant drop in the sample hardness.

Keywords

EN

81.05.Je   81.05.Mh   81.07.-b   81.20.-n   81.20.Ev   62.20.Qp   62.20.mm  

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2012
• Volume: 122
• Issue: 3
• Pages: 639-642

Dates

published

2012-09

References

• [1] G. Gille, B. Szesny, K. Dreyer, H. van den Berg, J. Schmidt, T. Gestrich, G. Leitner, Int. J. Refr. Metals Hard Mater. 20, 3 (2002)
• [2] Z.Z. Fang, X. Wang, T. Ryu, K.S. Hwang, H.Y. Sohn, Int. J. Refr. Metals Hard Mater. 27, 288 (2009)
• [3] H. Suzuki, in: Cemented Carbide and Sintered Hard Materials, Maruzen Publishing Company, Tokyo 1986, p. 262
• [4] FCT Systeme GmbH, webpages: http://www.fct-systeme.de/
• [5] L. Lutteroti, MAUD, IUCR Commission for Powder Diffraction, CPD Newsletter (IUCr), 21, 1999
• [6] D. Shetty, I.G. Wright, P.N. Mincer, A.H. Clauer, J. Mater. Sci 20, 1873 (1985)
• [7] M. Dopita, D. Rafaja, H.J. Seifert, D. Janisch, W. Lengauer, in: Proc. 17th Int. Plansee Seminar, Eds. L.S. Sigl, P. Rödhammer, H. Wildner, Vol. 3, AT4, Plansee Group, Reutte (Austria) 2009
• [8] M. Dopita, D. Rafaja, D. Chmelik, A. Salomon, D. Janisch, W. Lengauer, Materials Structure 18, 169 (2011)
• [9] H.-C. Kim, I.-J. Shon, J.E. Garay, Z.A. Munir, Int. J. Refr. Metals Hard Mater. 22, 257 (2004)
• [10] L. Girardini, M. Zadara, F. Casari, A. Molinari, Metal. Powder Report 63, 18 (2008)
• [11] S.G. Huang, K. Vanmeensel, O. van der Biest, J. Veleugels, Int. J. Refr. Metals Hard Mater. 26, 41 (2008)
• [12] J. Zhang, G. Zhang, A. Zhao, X. Song, J. Alloys Comp. 479, 427 (2009)
• [13] M. Dopita, C.R. Sriram, D. Chmelik, A. Salomon, H.J. Seifert, in: Proc. 2nd Int. Conf. NANOCON 2010, A46, Tanger Ltd., Ostrava (Czech Republic) 2010

Identifiers

DOI

10.12693/APhysPolA.122.639