Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-05T15:02:48.409Z Has data issue: false hasContentIssue false
  • English
  • Français

Optimization of heating schedules in pyrolytic binder removal from ceramic moldings

Published online by Cambridge University Press:  31 January 2011

J. H. Song ,
J. R. G. Evans ,
M. J. Edirisinghe  and
E. H. Twizell
J. H. Song
Affiliation:
Department of Materials Engineering, Brunel University, Uxbridge, Middlesex UB8 3PH, United Kingdom
J. R. G. Evans
Affiliation:
Department of Materials Engineering, Brunel University, Uxbridge, Middlesex UB8 3PH, United Kingdom
M. J. Edirisinghe
Affiliation:
Department of Materials Engineering, Brunel University, Uxbridge, Middlesex UB8 3PH, United Kingdom
E. H. Twizell
Affiliation:
Department of Mathematics and Statistics, Brunel University, Uxbridge, Middlesex UB8 3PH, United Kingdom
Get access

Abstract

A model that finds the maximum permissible heating rate for pyrolysis of ceramic moldings is extended to produce multi-segment temperature–time profiles to minimize the binder removal time. The degradation of the polymer and the diffusion of degradation products in solution to the free surface in a cylinder containing 50 vol% alumina and polyalphamethylstyrene is considered. The theory has previously been validated experimentally for fixed heating rates for cylindrical and flat plate geometries and for overpressure debinding. The extended model, presented here, calculates the vapor pressure of monomer over solution and modifies the heating rate to keep this just below ambient pressure. In this way, the temperature follows the maximum allowable rate at each stage to prevent boiling and hence the incidence of defects.

Type
Articles
Information
Journal of Materials Research , Volume 15 , Issue 2 , February 2000 , pp. 449 - 457
Copyright
Copyright © Materials Research Society 2000

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

1.Edirisinghe, M.J. and Evans, J.R. G., Int. J. High Tech. Ceram. 2, 1 and 249 (1986).CrossRefGoogle Scholar
2.Evans, J.R.G, in Processing of Ceramics Part I, Materials Science and Technology Series Vol. 17A, edited by Brook, R.J. (VCH, Weinheim, Germany, 1996), p. 267.Google Scholar
3.Greener, J. and Evans, J.R.G, J. Mater. Sci. 28, 6190 (1993).CrossRefGoogle Scholar
4.Williams, E.J.A.E and Evans, J.R.G, J. Mater. Sci. 31, 559 (1996).CrossRefGoogle Scholar
5.Haunton, K.M., Wright, J.K., and Evans, J.R.G, Br. Ceram. Trans. J. 89, 53 (1990).Google Scholar
6.Johnsson, A., Carlstrom, E., Hermansson, L., and Carlsson, R., Proc. Br. Ceram. Soc. 33, 139 (1983).Google Scholar
7.Huda, D., El Baradie, M.A., Hashmi, M.S.J, and Poyane, R., J. Mater. Sci. 33, 271 (1998).CrossRefGoogle Scholar
8.Stedman, S.J., Evans, J.R.G, and Woodthorpe, J., Ceram. Int. 16, 107 (1990).CrossRefGoogle Scholar
9.Saito, K., Tanaka, T., and Hibino, T., U.K. Patent No. 1426317 (25 February 1976).Google Scholar
10.Calvert, P. and Cima, M., J. Am. Ceram. Soc. 73, 575 (1990).CrossRefGoogle Scholar
11.Evans, J.R.G, Edirisinghe, M.J., Wright, J.K., and Crank, J., Proc. R. Soc. London A432, 321 (1991).Google Scholar
12.Matar, S.A., Edirisinghe, M.J., Evans, J.R.G, and Twizell, E.H., J. Am. Ceram. Soc. 79, 749 (1996).CrossRefGoogle Scholar
13.Hammond, P.D. and Evans, J.R.G, Chem. Eng. Sci. 50, 3187 (1995).CrossRefGoogle Scholar
14.Shaw, H.M. and Edirisinghe, M.J., Philos. Mag. A72, 267 (1995).CrossRefGoogle Scholar
15.Matar, S.A., Edirisinghe, M.J., Evans, J.R.G, Twizell, E.H., and Song, J.H., J. Mater. Sci. 30, 3805 (1995).CrossRefGoogle Scholar
16.Song, J.H., Evans, J.R.G, Edirisinghe, M.J., and Twizell, E.H., AICHE J. 42, 1715 (1996).CrossRefGoogle Scholar
17.Zhang, T., Evans, J.R.G, and Dutta, K.K., J. Eur. Ceram. Soc. 5, 303 (1989).CrossRefGoogle Scholar
18.Coulson, J.M. and Richardson, J.F., Chemical Engineering, 5th ed. (Butterworth Heinmann, Oxford, United Kingdom, 1996), Vol. 1, p. 368.Google Scholar
19.Holman, J.P., Heat Transfer (McGraw Hill, New York, 1963), p. 65.Google Scholar
20.Duda, J.L., Vrentas, J.S., Ju, S.T., and Lui, H.T., AIChE J. 28, 279 (1982).CrossRefGoogle Scholar
21.Lewis, J.A. and Galler, M.A., J. Am. Ceram. Soc. 79, 1377 (1996).CrossRefGoogle Scholar
22.Youngquist, G.R., D. Ind. Eng. Chem. 62, 53 (1970).Google Scholar
23.Song, J.H., Edirisinghe, M.J., Evans, J.R.G, and Twizell, E.H., J. Mater. Res. 11, 830 (1996).CrossRefGoogle Scholar
24.Twizell, E.H., Computational Methods for Partial Differential Equations (Ellis Horwood, Chichester, 1984), p. 203–204.Google Scholar
25.Smith, G.D., Numerical Solutions of Partial Equations: Finite Difference Methods, 3rd ed. (Oxford University Press, Oxford, United Kingdom, 1985), p. 326–328.Google Scholar