Toughening and Strengthening Mechanisms in Nanocomposites Based on Dislocation Activity

  • Hideo Awaji
  • Seong-Min Choi
Conference paper
Part of the Fracture Mechanics of Ceramics book series (FMOC, volume 14)

Abstract

Ceramics have low fracture toughness because dislocations are difficult to move in ceramics especially at room temperature. It is, therefore, hypothesized that a frontal process zone (FPZ) ahead of a crack tip is composed of many nano-cracks rather than dislocations as in metals.1,2 To overcome the inherent brittleness of ceramics, a new microstructural design concept must be developed. The design concept of “nanocomposites” is a new, and significantly improved strengths are achieved with moderate enhancement in fracture toughness. 3 The typical microstructure of nanocomposites consists of second-phase nano-size particles dispersed within the matrix grains. Thermal expansion mismatch between the matrix and second-phase particles improves several mechanical properties of nanocomposites.

Keywords

Residual Stress Fracture Toughness Tensile Residual Stress Critical Resolve Shear Stress Basal Slip 
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

© Springer Science+Business Media, Inc. 2005

Authors and Affiliations

  • Hideo Awaji
    • 1
  • Seong-Min Choi
    • 1
  1. 1.Nagoya Institute of TechnologyNagoyaJapan

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