Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-14T07:01:22.807Z Has data issue: false hasContentIssue false

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
Get access

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.

Type
Articles
Copyright
Copyright © Materials Research Society 2016 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

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