Microwave Hybrid Sintering of Nanostructured YSZ Ceramics


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Radiant and hybrid sintering experiments have been performed on dry and wet processed nanocrystalline 3-YSZ using both a conventional single stage and a new two stage sintering cycle. Whilst densities >98.5% of theoretical were achievable by all combinations, a nanostructure could only be retained using the two stage sintering approach. With hybrid heating the average grain sizes for die pressed samples were in the range 70 – 80 nm whilst for the more homogeneous slip cast samples a final average grain size of just 64 nm was achieved for a body with a final density of >99%. It is believed that the primary advantage offered by hybrid heating is the ability to use a much faster initial heating rate, 20 versus just 7oC min-1, without risking damage to the samples. Whilst detailed characterisation of the properties of these nanostructured ceramics is still underway, preliminary results have suggested that neither the hardness or toughness has been improved compared to conventional, submicron-sized 3-YSZ. As a result of detailed crystallographic characterisation this is believed to be due to a grain size dependent shift in the phase boundary composition for nano YSZ ceramics leading to ‘over stabilisation’ at any given yttria content.



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J. Binner et al., "Microwave Hybrid Sintering of Nanostructured YSZ Ceramics", Advances in Science and Technology, Vol. 45, pp. 835-844, 2006

Online since:

October 2006




[1] Mayo M, Int. Mater. Rev. 41 85 (1996).

[2] Groza JR, Int. J. Powder Met. 35.

[7] 59 (1999).

[3] Messing GL and Kumagai M, Am. Ceram. Bull. 73 88 (1994).

[4] Hahn H, Nanostr. Mater. 2 251 (1993).

[5] Rabe T and Wasche R, Nanostr. Mater. 6 357 (1995).

[6] Raghupathy B and Binner JGP, In Preparation.

[7] UK Patent application No. 0512666. 9. Binner JGP, Annapoorani K and Santacruz I, (2005).

[8] Santacruz MI, Binner JGP and Annapoorani K, In Preparation.

[9] Rahaman MN, in Sintering Technology, ed. GL Messing and RG Cornwall, p.93, Marcel Dekker, (1996).

[10] Hahn H, Averback RS, Hofler HJ and Logas J, Mater. Res. Symp. Proc. 206 569 (1991).

[11] Chen I & Wang X-H, Nature 404 168-171 (2000).

[12] Binner, JGP, Vaidhyanathan B, and Wang J, Proc. of the 9 th Int. Conf. on Microwave and High Frequency Heating, Loughborough, UK, 477-480 (2003).

[13] British Standards, Advanced Technical Ceramics - Monolithic Ceramics - General Textural Properties, Part 3, p.10, BS EN 623-3 (2001).

[14] Wang J, Binner J, Vaidhyanathan B, Joomun N, Kilner J, Dimitrakis G and Cross TE, In Press, J. Am. Ceram. Soc. (2006).

[15] Vaidhyanathan B and Binner JGP, Proc. Of 4th World Congress on Microwave and RF Applications, Publ. The Microwave Working Group, 192 - 198 (2005).