Microstructure and Mechanical Properties of W-ZrC Composites Synthesized by Reactive Melt Infiltration of Zr2Cu into Porous Preforms from Partially Carburized W Powders
W-ZrC composites with different W contents from 48 to 73 vol.% have been synthesized by reactive melt infiltration of Zr2Cu melt into porous preforms from partially carburized W powders at 1300 °C for 1 h in vacuum. The influences of carbon content and porosity in the preforms on microstructure and mechanical properties of W-ZrC composites are investigated. Cold isostatic pressing followed by pre-sintering process is used to produce porous preforms with suitable porosities of 53.6-47% under a pressure of 100 MPa to allow sufficient penetration of Zr2Cu melt into the preforms. Small amounts of Cu-rich phases form in the synthesized W-ZrC composites after a complete reaction of y/2xZr2Cu(l) + WC y (s) = y/xZrC x (s) + W(s) + y/2xCu(l). These Cu-rich phases are distributed not only at the phase boundaries of W matrix and ZrC grains, but also in the interior of ZrC x grains. With decreasing W content from 73 to 48 vol.% in the W-ZrC composites, the flexural strength and fracture toughness increase from 519 to 657 MPa and from 9.1 to 10.6 MPa m1/2, respectively.
Keywordsmechanical properties microstructure partially carburized W powders reactive melt infiltration W-ZrC composite
This work was financially supported by the National Natural Science Foundation of China (Nos. 51621091, 51172052 and 51472060) and Program for New Century Excellent Talents in University (No. NCET-13-0177).
- 1.K. Upadhya, J.-M. Yang, and W.P. Hoffman, Materials for Ultrahigh Temperature Structural Applications, Am. Ceram. Soc. Bull., 1997, 76(12), p 51–56Google Scholar
- 5.E. Lassner and W.-D. Schubert, Tungsten: Properties, Chemistry, Technology of the Element, Alloys, and Chemical Compounds, Springer, Berlin, 2012Google Scholar
- 13.B. Metals, Ceramics Information Center, Engineering Data on Selected Ceramics, Vol II, Carbides Battelle Columbus Laboratories, Columbus, 1979Google Scholar
- 14.A.E. Mchale, Phase Equilibria Diagrams, American Ceramic Society, Westerville, 1994Google Scholar
- 15.Y. Touloukian, R. Kirby, R. Taylor, and P. Desai, Thermophysical Properties of Matter-the TPRC Data Series. Volume 12. Thermal Expansion Metallic Elements and Alloys, Plenum Press, New York, 1975, p 354Google Scholar
- 16.Y.S. Touloukian, R. Kirby, E. Taylor, and T. Lee, Thermophysical Properties of Matter-the TPRC Data Series. Volume 13. Thermal Expansion-Nonmetallic Solids, Plenum Press, New York, 1977, p 926Google Scholar
- 17.I. Barin and G. Platzki, Thermochemical Data of Pure Substances, Wiley Online Library, Weinheim, 1989, p 1788Google Scholar
- 23.D. Ye and J. Hu, Practical Handbook of Energetic Data for Inorganic Compounds, Metallurgical industry press, Beijing, 2002, p 1204Google Scholar
- 30.M.B. Dickerson, R.R. Unocic, K.T. Guerra, M.J. Timberlake, and K.H. Sandhage, Fabrication of Dense Carbide/Refractory Metal Composites of Near Net Shape at Modest Temperatures by the Prima-DCP Process, Ceram. Trans., 2000, 115, p 25–31Google Scholar
- 33.H.O. Pierson, Handbook of Refractory Carbides and Nitrides, Elsevier, Amsterdam, 1996, p 106Google Scholar
- 41.W.D. Klopp, and W.R. Witzke, Mechanical Properties and Recrystallization Behavior of Electron-Beam-Melted Tungsten Compared with Arc-Melted Tungsten, NASA TN D-3232, Lewis Research Center, Cleveland, Ohio, 1966, p 1–34Google Scholar