Cordierite composites

FIGURE 13.2 Scaiming electron micrographs of fractnre snrfaces of cordierite composition gels sintered at 1300°C for 2 h (a) nanocomposite and (b) homogeneons (single phase). (Reprinted with permission from Kazakos, A.M., Komameni, S., and Roy, R., J. Mater. Res., 5, 1095, 1990.)... 

The initial substrates in 1975, with square cell configuration, were designed to have 200 cells/in. with a wall thickness of 0.012 in. They were extruded from cordierite composition (EX-20), which had a fired wall porosity of 35%. Similarly, the triangular cell substrates had a cell density of 236 cells/in. and a wall thickness of 0.0115 in. They were extruded from a lowcr-CTE cordierite composition (EX-32), with a fired wall porosity of 40%. The geometric properties of these two substrates, as well as current versions of square cell substrates with cell density of 3(X) and 4(X) cells/in. are summarized in Table 1. 

The cordierite composition minimizes thermal fracture from these stresses by virtue of a low coefficient of thermal expansion. Resistance to thermal fracture has been noticeably improved in recent years largely the result of ... 

The primary objective of designing a ceramic preconverter system for light-otf application has been met by proper selection of cordierite composition, cell geometry, substrate contour, size and volume, high temperature durable mat, and a robust packaging design. 

The low porosity cordierite composition, EX-22, with two unique cell geometries, is rec-... 

Travitzky, N. A., Mechanical Properties and Microstmcture of Mullite Whisker-Reinforced Magnesiitm Aluminosilicate Glass with Cordierite Composition, 7. Mat. Sci. Lett. 17 (1998) 1609-1611. 

Aluminum titanate composition Cordierite composition Silicon carbide... 

The data of Fig. 8 are very different from those of Fig. 6 and suggest a much more variable interaction between an extending crack and the microstructure over the range of crack extensions examined. The cordierite composite data suggest an... 

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