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Influence of Sintering Conditions on the Microstructure and Properties of Alumina-Filled Borosilicate Glass
P.F. Araújo1, L.B. Daros1, M. Souza1, D.E. García1, D. Hotza1,2
1 Graduate Program on Materials Science and Engineering (PGMAT)
2 Department of Chemical Engineering (EQA) 88040 - 900 Florianópolis, SC, Brazil
received August 26, 2015, received in revised form November 3, 2015, accepted January 8, 2016
Vol. 7, No. 1, Pages 119-126 DOI: 10.4416/JCST2015-00048
Abstract
Alumina-filled borosilicate glass composites (1-x) glass + xAl2O3 (x = 0, 5, 10, 15, 20 vol%) were fabricated by means of conventional sintering at 800 and 850 °C and fast firing at temperatures between 850 and 950 °C. The effect of particle size, heating rate and holding time at maximum temperature on phase composition and densification was investigated. The effect of Al2O3 addition on microstructure, flexural strength, fracture toughness, electrical conductivity, and thermal expansion coefficient is reported. Al2O3 hinders the formation of cristobalite and enhances the mechanical properties of borosilicate glass. Composites containing 10 vol% alumina fabricated by means of conventional sintering exhibited 98 % TD, flexural strength of 175 MPa and fracture toughness of 1.9 MPa·m1/2. Crack path and fracture surface observations showed that crack deflection, crack bridging and pull-out by alumina particles were responsible for the increase in fracture toughness. Samples fabricated by means of fast firing exhibited a decrease in flexural strength of ∼ 50 % and an increase in fracture toughness of ∼ 40 % when compared to conventional sintering. This behaviour could be related to the presence of microcracks originating from β-to-α cristobalite transformation during rapid cooling from the sintering temperature. In conventionally sintered samples, the addition of 5 vol% alumina to borosilicate glass increases hardness from 4.7 to 5.6 GPa, and the dielectric constant from 5.5 to 6.5.
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Keywords
Alumina, borosilicate glass, ceramic-filled glasses, fast firing, sintering
References
1. Pascual, M.J., Pascual, L., Durán, A.: Modelling of sintering process in borosilicate glasses with rigid inclusions. European Society of Glass Science and Technology, Universite des sciences et techniques du Languedoc; Institut du Verre; International Commission on Glass, in: ESG conference; Glass odyssey 6th, ESG conference, 2002.
2. Kingery, W.D., Bowen, H.K., Uhlmann, D.R.: Introduction to ceramics, 2nd ed. New York: John Wiley & Sons, 1976.
3. Ewsuk, K.G., Harrinson, L.W., Walczak, F.J.: Sintering glass-filled ceramic composites; effects of glass properties. Ceramic Powder Science II, Part B, Ceramic Transactions, edited by Messing, G.L., Fuller, E.R. Westerville, OH: The American Ceramic Society, Inc., 1, 969 – 977, 1988.
4. Harrison, L.W., Ewsuk, K.G.: Processes for manufacturing tailored property ceramic composites, in design for manufacturability and manufacture of ceramic components, Westerville, OH: The American Ceramic Society, Inc., Ceram. Trans., 49, 197 – 219, 1995.
5. Ewsuk, K.G., Harrinson, L.W.: Densification of glass-filled alumina composites, in: Sintering of Advanced Ceramics, Ceramic Transactions, edited by Handwerker, C., Blendell, J., Kaysser, W.A., Westerville, OH: The American Ceramic Society, Inc., 7, 438 – 451, 1990.
6. Park, S.J., Lee, S.J.: Mechanism of preventing crystallization in low-firing glass/ceramic composite substrates, J. Am. Ceram. Soc., 78, [4], 1128 – 1130, (1995).
7. Jean, J.H., Kuan, T.H.: Crystallization inhibitors during sintering of pyrex borosilicate glass, J. Mater. Sci. Lett., 14, 1068 – 1070, (1995).
8. Lambrinou, K., Biest, O.V., Boccaccini, A.R., Taplin, D.: Densification and crystallisation behaviour of barium magnesium aluminosilicate glass powder compacts. J. Eur. Ceram. Soc., 16, [11], 1237 – 1244, (1996).
9. Zawrah, M.F., Hamzawy, E.M.A.: Effect of cristobalite formation on sinterability, microstructure and properties of glass/ceramic composites, Ceram. Int., 28, 123 – 130, (2002).
10. Holand, W., Beall, G.: Glass-ceramics technology. 1st ed. Westerville, OH: The American Ceramic Society, Inc., 2002.
11. Bernardo, E., Scarinci, G.: Sintering behaviour and mechanical properties of Al2O3 platelet-reinforced glass matrix composites obtained by powder technology, Ceram. Int., 30, 785 – 791, (2004).
12. El-Kheshen, A.A.: Effect of alumina addition on properties of glass/ceramic composite, Brit. Ceram. Trans., 102, [5], 205 – 209, (2003).
13. Liu, M., Hongqing, Z., Haikui, Z., Zhenxing, Y., Jianxin, Z.: Microstructure and dielectric properties of glass/Al2O3 composites with various low softening point borosilicate glasses, J. Mater. Sci.: Mater. Electron., 23, 2130 – 2139, (2012).
14. Ray, A., Tiwari, A.N.: Compaction and sintering behaviour of glass-alumina composites, Mater. Chem. Phys., 67, 220 – 225, (2001).
15. Kagawa, Y., Kogo, Y., Hatta, H.: Thermal expansion behavior of the si, N-whisker-reinforced soda-borosilicate glass matrix composite, J. Am. Ceram. Soc., 72, [6], 1092 – 1094, (1989).
16. Chinnam, R.K., Boccaccini, A.R., Bernardo, E., Epstein, H.: Glass-ceramic composites from borosilicate glass and alumina-rich residues, J. Appl. Ceram. Tech., 12, [S2], E19 – E27, (2015).
17. Boccaccini, A.R., Janczak-Rusch, J., Pearce, D.H., Kern, H.: Assessment of damage induced by thermal shock in SiC-fiber-reinforced borosilicate glass composites, Compos. Sci. Technol., 59, 105 – 112, (1999).
18. Klug, T., Bruckner, R.: Preparation of C-fibre borosilicate glass composites: influence of the fibre type on mechanical properties, J. Mater. Sci., 29, 4013 – 4021, (1994).
19. Duran, A., Pascual, M.J., Pascual, L.: Sintering behaviour of composite materials borosilicate glass-ZrO2 fibre composite materials, J. Eur. Ceram. Soc., 22, 1513 – 1524, (2001).
20. Hasanuzzaman, M., Sajjia, M., Rafferty, A., Olabi, A.G.: Thermal behaviour of zircon/zirconia-added chemically durable borosilicate porous glass, Thermochim. Acta, 555, 81 – 88, (2013).
21. Lim, W.B., Saji, V.S., Cho, Y.S., Shul, Y.G., Lim, S., Jang, J.H., Lee, H.R.: Crystallization and dielectric properties of low temperature dielectrics containing Li2O filler, J. Non-Cryst. Solids, 354, 3849 – 3853, (2008).
22. Jean, J., Gupta, T.K.: Effect of alumina on densification of binary borosilicate glass composite, J. Mater. Res., 9, [8], 1990 – 1996, (1994).
23. Monteiro, R.C.C., Lima, M.M.R.A.: Effect of compaction on the sintering of borosilicate glass/alumina composites, J. Eur. Ceram. Soc., 23, 1813 – 1818, (2003).
24. Lima, M.M.R.A., Monteiro, R.C.C., Graça, M.P.F., Ferreira Da Silva, M.G.: Structural, electrical and thermal properties of borosilicate glass-alumina composites. J. Alloy. Compound., 538, 66 – 2, (2012).
25. Boccaccini, A.R., Trusty, P.A.: Toughening and strengthening of glass by Al2O3 platelets, J. Mater. Sci. Lett., 15, 60 – 63, (1996).
26. Lawn, B.R., Fuller, E.R., Wiederhorn, S.M.: Strength degradation of brittle surfaces: sharp indenters, J. Am. Ceram. Soc., 59, [5 – 6], 193 – 97, (1976).
27. Lima, M.M., Monteiro, R.: Characterization and thermal behaviour of a borosilicate glass, Thermochim. Acta, 373, 69 – 74, (2001).
28. Boccaccini, A.R.: On the viscosity of glass composites containing rigid inclusions, J. Mater. Lett., 34, 285 – 289, (1999).
29. Boccaccini, A.R., Olevsky, E.A.: Processing of platelet-reinforced glass matrix composites: effect of inclusions on sintering anisotropy, J. Mater. Process. Tech., 96, 92 – 101, (1999).
30. Cheng-Hua, K., Gupta, P.K.: Rigidity and conductivity percolation threshold in particulate composites, Acta Metall. Mater., 43, 397 – 403, (1995).
31. García, D.E., Klein, A.N., Hotza, D.: Advanced ceramics with dense and fine-grained microstructures through fast firing, Rev. Adv. Mater. Sci., 30, 273 – 281, (2012).
32. Possamai, T.S., Oba, R., Nicolau,V.P., Hotza, D., García, D.E.: Numerical simulation of the fast firing of alumina in a box furnace, J. Am. Ceram. Soc., 95, [12], 3750 – 3757, (2012).
33. Zawrah, M.F.M., El-Kheshen, A.A.: Characterisation of borosilicate glass matrix composites reinforced with SiC or ZrO2, Brit. Ceram. Trans., 103, [4], 165 – 170, (2004).
34. Chang-Jun, B.: Integrally cored ceramic investment casting mold fabricated by ceramics, Int. J. Appl. Ceram. Technol., 8, [6], 1255 – 1262, (2011).
35. Claussen, N., Steeb, J.: Toughening of ceramic composites by oriented nucleation of microcracks, J. Am. Ceram. Soc., 59, 457 – 458, (1976).
36. Miyata, N., Akada, S., Omura, H., Jinno, H.: Microcrack toughening mechanism in brittle matrix composites. In: Bradt, R.C., Hasselman, D.P.H., Munz, D., Sakai, M., Shevchenko, V. YA. (Ed.). Fracture mechanics of ceramics: Springer US, 9, [24], 339 – 355, 1992.
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