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The paper reviews the wear behaviour of oxide ceramics. Wear maps are considered and consequently mild and severe wear are defined. Since the use of ceramics in engineering applications require operation in the mild wear regime, the paper concentrates on mild wear mechanisms, but also considers factors which control the transition to severe wear. Within the mild wear regime, the formation of tribofilms are discussed and the manner in which dislocation activity leads to the wear transition is considered. The wear of so-called ceramic nanocomposites, for which no time dependent wear transition has yet been observed, is considered and the reasons for enhanced performance discussed. The role of transformation toughening in zirconia ceramics is considered in detail, and reasons for the generally poor wear response of these materials defined. [ABSTRACT FROM AUTHOR]

The red glaze (slip) that characterizes the Terra Sigillata potteries, greatly contributed to their success during the Roman period. This feature can in fact be partially explained by the microstructure (crystalline phases and grain sizes) and the physico-chemistry (compositions) of the ceramics. In this paper, we describe how the technique of synchrotron micro scanning X-raydiffraction could contribute to the understanding of the elaboration process and origins of these ceramics. The small (micron) size of the X-raybeam coupled with the use of a sample scanning stage allows one to spatially resolve the distribution and other characteristics of the constitutive mineral phases. [ABSTRACT FROM AUTHOR]