By introducing ZrO 2 and Y 2 O 3 mixed powder into the thermit, the large-scale Al 2 O 3 /ZrO 2 (Y 2 O 3 ) self-growing ceramic plates were prepared from the melts through combustion synthesis under high gravity. The materials were mainly formed by randomly-orientated rod-shaped colonies with faceted structures consisting of a triangular dispersion of orderly nanosubmicron ZrO 2 fibers in the Al 2 O 3 matrix, surrounded by the boundary regions that contained the coarse irregularshaped ZrO 2 and Al 2 O 3 phases. The flexural strength of the self-growing ceramic plate was excellent (measured 1278MPa), and it was not only attributed to the small critical defect size caused by the fine eutectic microstructures, excellent bonding between the Al 2 O 3 /ZrO 2 phases and the thin inter-colony regions, but also more importantly dependent on high fracture toughness of 13.7 MPa·m 1/2 , which is controlled by residual compressive stress toughening in the colonies, transformation induced toughening and transformation induced microcrack toughening mechanisms in intercolony regions during crack propagation.

The first three significant digits of a sample's refractive index are compensated by a standard, therefore a precise measurement, which is the same as the refractive index of the standard, can be obtained. The method only needs a thin sample.

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Abstract. TiB 2 -TiC-Ni composites were achieved through direct reaction of Ti and B 4 C powder blends in a high gravity field of 1800 g with Ni binder. The microstructure of TiB 2 -TiC composites present pore-free with darker TiB 2 platelets and the brighter TiC equiaxed grains easily distinguishable. Ti-B-C-Ni full-liquid SHS intermediate products immediately were formed following the reaction of Ti and B 4 C, which was considered to yield inherently finegrained microstructures under the rapid cooling condition. The role of high gravity field was proposed as promoter of the final products densification and grain refinement of TiB 2 -TiC composites.

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