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Effect of applied pressure on densification of monolithic ZrCx ceramic by reactive hot pressing

Published online by Cambridge University Press:  16 February 2016

Lingappa Rangaraj*
Affiliation:
Materials Science Division, CSIR-National Aerospace Laboratories, Bangalore 560017, Karnataka, India
Tamoghna Chakrabarti
Affiliation:
Department of Materials Engineering, Indian Institute of Science, Bangalore 560012, Karnataka, India
Rajaguru Kannan
Affiliation:
Materials Science Division, CSIR-National Aerospace Laboratories, Bangalore 560017, Karnataka, India
Vikram Jayaram
Affiliation:
Department of Materials Engineering, Indian Institute of Science, Bangalore 560012, Karnataka, India
*
a)Address all correspondence to this author. e-mail: ranga@nal.res.in
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Abstract

The effect of applied pressure on reactive hot pressing (RHP) of zirconium (Zr):graphite (C) in molar ratios of 1:0.5, 1:0.67, 1:0.8, and 1:1 was studied at 1200 °C for 60 min. The relative density achievable increased with increasing pressure and ranged from 99% at 4 MPa for ZrC0.5 to 93% for stoichiometric ZrC at 100 MPa. The diminishing influence of pressure on the final density with increasing stoichiometry is attributed to two causes: the decreasing initial volume fraction of the plastically deforming Zr metal which leads to the earlier formation of a contiguous, stress shielding carbide skeleton and the larger molar volume shrinkage during reaction which leads to pore formation in the final stages. A numerical model of the creep densification of a dynamically evolving microstructure predicts densities that are consistent with observations and confirm that the availability of a soft metal is primarily responsible for the achievement of such elevated densification during RHP. The ability to densify nonstoichiometric compositions like ZrC0.5 at pressures as low as 4 MPa offers an alternate route to fabricating dense nonstoichiometric carbides.

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Articles
Copyright
Copyright © Materials Research Society 2016 

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References

REFERENCES

Weimer, A.W.: Carbide, Nitride and Boride Materials Synthesis and Processing (Chapman and Hall Publications, London, 1997).Google Scholar
Pierson, H.: Handbook of Refractory Carbides & Nitrides (Noyes Publications, Westwood, NJ, USA, 1996).Google Scholar
Toth, L.E.: Transition Metal Carbides and Nitrides (Academic Press, New York, 1971).Google Scholar
Storms, E.K.: The Refractory Carbides (Academic Press, New York, 1967).Google Scholar
Adamovskii, A.: Carbides of transition metals in abrasive machining (Review). Powder Metall. Met. Ceram. 46(11), 595 (2007).Google Scholar
Vasudevamurthy, G., Knight, T.W., Roberts, E., and Adams, T.M.: Laboratory production of zirconium carbide compacts for use in inert matrix fuels. J. Nucl. Mater. 374(1–2), 241 (2008).Google Scholar
Barnier, P., Brodhag, C., and Thevenot, F.: Hot-pressing kinetics of zirconium carbide. J. Mater. Sci. 21(7), 2547 (1986).Google Scholar
Lanin, A.G., Marchev, E.V., and Pritchin, S.A.: Non-isothermal sintering parameters and their influence on the structure and properties of zirconium carbide. Ceram. Int. 17, 301 (1991).CrossRefGoogle Scholar
Nachiappan, C., Rangaraj, L., Divakar, C., and Jayaram, V.: Synthesis and densification of monolithic zirconium carbide by reactive hot pressing. J. Am. Ceram. Soc. 93(5), 1341 (2010).Google Scholar
Sara, R.V.: The system zirconium—Carbon. J. Am. Ceram. Soc. 48, 243 (1965).CrossRefGoogle Scholar
Massalski, T.B. and Okamoto, H.: Binary Alloy Phase Diagrams (ASM International, Materials Park, OH, 1990).Google Scholar
Rangaraj, L., Suresha, S.J., Divakar, C., and Jayaram, V.: Low-temperature processing of ZrB2-ZrC composites by reactive hot pressing. Metall. Mater. Trans. A 39(7), 1496 (2008).Google Scholar
Wang, X., Guo, W.M., Kan, Y.M., Zhang, G.J., and Wang, P.L.: Densification behavior and properties of hot-pressed ZrC ceramics with Zr and graphite additives. J. Eur. Ceram. Soc. 31, 1103 (2011).Google Scholar
Chakrabarti, T., Rangaraj, L., and Jayaram, V.: Effect of zirconium on the densification of reactively hot pressed zirconium carbide. J. Am. Ceram. Soc. 97(10), 3092 (2014).Google Scholar
Chakrabarti, T., Rangaraj, L., and Jayaram, V.: Computational modelling of reactive hot pressing of zirconium carbide. J. Mater. Res. 30(12), 1876 (2015).Google Scholar
Chakravartty, J.K., Banerjee, S., and Prasad, Y.V.R.K.: Super-plasticity in β-zirconium: A study using a processing map. Scr. Metall. Mater. 26(1), 75 (1992).Google Scholar
Zwigl, P. and Dunand, D.C.: Transformation superplasticity of zirconium. Metall. Mater. Trans. A 29(10), 2571 (1998).Google Scholar
Chakravartty, J.K., Prasad, Y.V.R.K., and Asundi, M.: Processing map for hot working of alpha-zirconium. Metall. Trans. A 22(4), 829 (1991).CrossRefGoogle Scholar
Sheshadri, R., Narayanaswamy, V., Dwarakanatha Rao, B., and Rangaraj, L.: Design and fabrication of laboratory model uni-axial hot press. In Advances in High Pressure Science and Technology, Singh, A.K. ed.; Tata McGraw-Hill: New Delhi, 1995.Google Scholar
Lutterotti, L.: Total pattern fitting for the combined size-strain-stress-texture determination in thin film diffraction. Nucl. Instrum. Methods Phys. Res., Sect. B 268(3–4), 334 (2010).Google Scholar
Lutterotti, L., Bortolotti, M., Ischia, G., Lonardelli, I., and Wenk, H.R.: Rietveld texture analysis from diffraction images. Z. Kristallogr. 26, 125 (2007).Google Scholar
Helle, A.S., Easterling, K.E., and Ashby, M.F.: Hot-isostatic pressing diagrams-new developments. Acta Metall. 33(12), 2163 (1985).Google Scholar
Duva, J.M.: A self-consistent analysis of the stiffening effect of rigid inclusions on a power-law material. J. Eng. Mater. Technol. 106(4), 317 (1984).Google Scholar
Dong, M. and Schmauder, S.: Modeling of metal matrix composites by a self-consistent embedded cell model. Acta Mater. 44(6), 2465 (1996).Google Scholar
Schmalzried, H.: Solid State Reactions (Academic Press, New York, USA, 1974).Google Scholar
Sargent, P.M. and Ashby, M.F.: Deformation maps for titanium and zirconium. Scr. Metall. 16(12), 1415 (1982).Google Scholar
Knorr, D.B. and Notis, M.R.: Deformation mechanism mapping of α-Zr and zircaloy-2. J. Nucl. Mater. 56(1), 18 (1975).Google Scholar
Guillermet, A.F.: Analysis of thermo-chemical properties and phase stability in the zirconium-carbon system. J. Alloys Compd. 217, 69 (1995).Google Scholar
Hugosson, H.W., Jansson, U., Johansson, B., and Eriksson, O.: Phase stability diagrams of transition metal carbides: A theoretical study. Chem. Phys. Lett. 333, 444 (2001).Google Scholar