Damage behavior of ceramic materials by impact

Ceramic materials have been a promising candidate for structural materials under sever conditions. In 1994, the authors published a review paper on impact damage of ceramic materials. In/before that period, the main topics of published papers were on erosion behaviour of ceramics impacted by small objects at relatively low velocities and on postmortem observation/measurements. In this decade, however, progressive improvements of in situ observation/measuring techniques provided many important and useful visible/numerical results concerning the impact on ceramics. Therefore, this paper summarizes achieved results that mainly appeared in the last decade, concerning following topics; Impact damage, fracture and/or strength of ceramics including glasses and graphites. This survey reveals that the trends on research topics seemed to change in this decade: Papers on low-velocity erosion decreased, those on high-velocity were published, and results based on scientifically quantitative analyses were presented. Most important thing is that a concept of "fracture wave" and the wave itself was found out. The mechanisms and the modeling, however, remain unclear because of insufficient number of precise measurements associated with their detailed observation of the related phenomena for ceramics. Precise and detailed observation on damage/fracture behaviour, based on a time-place sequence of damage/crack initiation and propagation, is necessary in the whole specimen's response.