Processing of High Hardness-high Toughness Alumina Matrix Nanocomposites

Abstract

Ceramic-matrix composites with nanocrystalline (grain size less than 100 nm) matrix provide new opportunities, both scientific and technological. Fully dense nanocrystalline alumina matrix composites with grain size as fine as 40 nm has been synthesized. The results show significantly higher hardness and toughness in nanocomposites. The hardness values of fully dense nanocrystalline Al O3-10 vol.% Nb composite range from 20 to 23 GPa. The indentation toughness of Al2O3-10 vol.% Nb sintered at 900°C and 2 GPa for 60 min is >8 MPa m1/2. The present results show an increase in fracture toughness by more than 250% while retaining the hardness as compared with microcrystalline single-phase alumina.

Department(s)

Materials Science and Engineering

Sponsor(s)

National Science Foundation (U.S.)

Keywords and Phrases

Alumina; Hardness; High Pressure Sintering; Toughening

International Standard Serial Number (ISSN)

0921-5093

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2001 Elsevier, All rights reserved.

Publication Date

01 Mar 2001

Share

 
COinS