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Atomic Crack Tips in Covalent Crystal

  • Hidehiko Tanaka
  • Yoshio Bando
  • Mamoru Mitomo
  • Yoshizo Inomata

Abstract

Crack tip geometries in covalent crystals were studied by high resolution (HR) TEM. The materials used in the study were SiC, Si crystals and 15R-sialon grain. Cracks were introduced by Vickers indentation in SiC and Si. In 15R-sialon, crack was naturally introduced. It was found that the crack tips were atomically sharp and there was no macroscopic yielding zone. The results of TEM observation are summarized here.

Keywords

Dislocation Segment Sharp Crack Vickers Indentation Covalent Crystal Cleavage Crack Propagation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Elsevier Science Publishers Ltd. 1990

Authors and Affiliations

  • Hidehiko Tanaka
    • 1
  • Yoshio Bando
    • 1
  • Mamoru Mitomo
    • 1
  • Yoshizo Inomata
    • 1
  1. 1.National Institute for Research in Inorganic MaterialsTsukubashi IbarakikenJapan

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