Mullite composites

Yoon, C.K. and Chen, I.W. Superplasticity of two-phase ceramics containing inclusions - zirconia mullite composites , J. Am. Ceram. Soc. 73 (1990) 1555-1565. 

T. N. Tiegs, P. F. Becher, and P. Angelini, Microstructures and Properties of SiC Whisker-Reinforced Mullite Composites, in Mullite and Mullite Matrix Composites, Ceramic Transactions, Vol. 6, eds. S. Somiya, R. F. Davis, and J. A. Pask, American Ceramic Society, Westerville, OH, 1990, pp. 463-472. 

C. K. Yoon and I.-W. Chen, Superplastic Flow of Two-Phase Ceramics Containing Rigid Inclusions-Zirconia/Mullite Composites, J. Am. Ceram. Soc., 73[6], 1555-1565 (1990). 

FIGURE 13.1 Transmission electron micrographs of mullite composition gels (a) nanocomposite and (b) homogeneons (single phase). 

Figure 4.27. Changes in the Si spectra of A. monophasic, and B. diphasic gels of mullite composition on heating. Note the predominantly aluminosilicate resonance (— 85 ppm) in the monophasic gel at lower temperatures, compared with the predominantly siliceous resonance (— 108 ppm) in the diphasic gel. From Jaymes et al. (1996), by permission of copyright owner.

Figure 4.28. spectrum of a dark-coloured mullite-composition aluminosilicate gel heated in... 

Figure 4.29. Effect of grinding on the Si spectra of the alumina-silica system. A. Mixture of gibbsite, Al(OH)3 and silica gel, and B. Diphasic gel of mullite composition. Note in both systems the evidence of Si-O-Al bond formation (peak at about — 84 ppm). Adapted from Temuujin et al.

Figure 5.10. MAS NMR spectra of a number of amorphous aluminosilicates of approximately mullite composition derived from various sources, showing the peak at ca.30 ppm attributed to Al (arrowed). From McManus et al. (2001), by permission of Elsevier Science.

D Al MQ MAS NMR is used to extract the isotropic chemical shifts and quadmpolar parameters of five amorphous aluminosilicates, all of approximately mullite composition (3Al(2)0(3).2Si0(2)) but of widely differing synthetic origin. Three principal types of A1 site are apparent in each sample two of these are conventionally assigned to 4- and 6-coordinate Al, while the nature of the third site, observed at a shift of delta approximate to 30 ppm, remains a subject of debate. ... 

Mullite powders obtained by various methods can first be crystallized near 1,200°C, and then sintered at temperatures below the eutectic. Highly pure mullite and mullite composites have been obtained by hot pressing below 1,300°C with this method [34],... 

Nath, S., Basu, B., Mohanty, M., and Mohanan, P.V. (2009) In vivo response of novel calcium phosphate-mullite composites results up to 12 weeks of implantation. /. Biomed. Mater. Res. Part B, 90 (2), 547-557. 

NANO-ZIRCONIA/MULLITE COMPOSITE CERAMICS PREPARED BY IN-SITU... 

Keywords Si-Al-Zr-O amorphous bulk crystallization, Zirconia-mullite composite structure, mechanical property... 

Recently, some other non- conventional ways have been used to prepare zirconia-mullite ceramics [12-17]. In our previous work, nano-zirconia/mullite composite ceramics were prepared by in-situ controlled crystallization from the Si-Al-Zr-0 amorphous bulk, the crystallization kinetics and the general view on the performance were discussed for the first time. In this article, the detail crystallization behavior, structure changes and their effect on mechanical properties for this new nano composite ceramics with high performance have been evaluated. 

Nano-Zirconia/Mullite Composite Ceramics Prepared by In-Situ Controlled Crystallization... 

Khor K A, Yu L G, Li Y. Spark plasma reaction sintering of Zr02 mullite composites from plasma sphe-roidized zircon/ alumina powers. Mater Sci Eng A, 2003, 339 (12) 286-296,... 

NANO-ZIRCONIA/MULLITE COMPOSITE CERAMICS PREPARED 99 BY IN-SITU CONTROLLED CRYSTALLIZATION FROM THE Si-AI-Zr-0 AMORPHOUS BULK... 

The slurry process can also be used to produce composites by tape casting. An example is the fabrication of laminated SiC whisker-reinforced mullite composites. 

Katsuki H, Furuta S, Komameni S. Formation of novel ZSM-5/porous mullite composite from sintered kaolin honeycomb by hydrothermal reaction. JAm Ceram Soc 2000 83(5) 1093-1097. 

The electrical behavior of hot-pressed mullite composites reinforced with 10, 20 and 30% SiC whiskers was evaluated in the 100 Hz to 10 MHz frequency range. Samples... 

A. Hynes, R. H. Doremus, R. Ruh, Y. Xu, and A. Zangvil, Creep of Mullite Composites Containing Zirconia and Silicon Carbide Whiskers pp. 509-21 in Advances in Ceramic Matrix Composites III, Ceramic Transactions, Vol. 74. Edited by N. P. Bansal and J. P. Singh. The American Ceramic Society, Westerville, OH, 1996. 

J. She, P. Mechnich, H. Schneider, M. Schmiicker, B. Kanka, Effect of cyclic infiltrations on microstmcture and mechanical behavior of porous mullite/mullite composites. Mat. Sci. Engg. A325 19-24 (2002). 

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