著者
大熊 学 渡辺 修平 篠部 寛 西山 宣正 竹内 晃久 上杉 健太郎 田中 諭 若井 史博
出版者
一般社団法人 粉体粉末冶金協会
雑誌
粉体および粉末冶金 (ISSN:05328799)
巻号頁・発行日
vol.66, no.12, pp.604-610, 2019-12-15 (Released:2019-12-15)
参考文献数
40

The characterization of the processing-induced defects is a significant step for developing defect-free processing, which is important to the assurance of the mechanical reliability of brittle ceramics. Recent advances in multiscale X-ray computed tomography which consists of micro-CT and nano-CT enables us to observe the three-dimensional (3D) internal structure non-destructively. Micro-CT reveals the distribution of defects in the entire body of a sample, while nano-CT reveals the shape of the identified defect. This powerful imaging tool was used to reveal the complicated 3D morphology of defects evolved during sintering of alumina. The hierarchical packing structure of granules was the origin of several types of strength-limiting defects, which could not be eliminated due to the differential sintering of heterogeneous microstructures. This imaging technique of internal defects provides a link between the processing and the fracture strength for the development of structural materials.
著者
佐藤 和好 佐藤 匠海 武蔵 徳明 田中 諭 内田 希 植松 敬三
出版者
公益社団法人日本セラミックス協会
雑誌
日本セラミックス協会学術論文誌 : Nippon Seramikkusu Kyokai gakujutsu ronbunshi (ISSN:18821022)
巻号頁・発行日
vol.109, no.1276, pp.1055-1056, 2001-12-01
被引用文献数
1

A confocal scanning laser microscope (CSLM) was applied to identify the location of fracture origin in alumina ceramics. Alumina-referceram was ground to obtain JIS R-1601 specimens using a grinding machine. They were fractured in four point bending to measure strength. CSLM and scanning electron microscope (SEM) micrographs of fracture surface were compared. With a CSLM, the location of fracture origin could be easily determined, while it was very difficult with a SEM. Fracture toughness K_<IC>=2.3MPa ・ m^<1/2> ealculated from the measured size of fracture origin and the flexural strength