Pressureless Sintering of B₄C Whisker Reinforced Al₂O₃ Matrix Composites

Author

Xuan Lin
P. D. Ownby, Missouri University of Science and TechnologyFollow

Abstract

Al₂O₃-B₄C whisker composites have been successfully densified by pressureless sintering. Low oxygen partial pressures, below 10^-10 atmospheres, were determined to be suitable for the composite densification, and the maximum densities were achieved at 1800 ⁰C for 60 minutes. The B₄C whiskers were screened classified into five size fractions and the effect of size and size distribution on the densification were studied. The small whiskers with a narrow size distribution (-325 + 400 mesh) yielded the highest density results. The maximum value of relative densities was 98%, 97%, 94% and 89% at 10, 20, 30 and 40 vol % B₄C whiskers, respectively. Addition of B₄C between 5 and 15 vol % proved to be a sintering aid to the alumina densification via mechanisms other than being a grain growth inhibitor. An increased fracture toughness up to 6.2 MPa·m ^1/2 was achieved in the composites containing 10-20 vol % B₄C whiskers.

Recommended Citation

X. Lin and P. D. Ownby, "Pressureless Sintering of B₄C Whisker Reinforced Al₂O₃ Matrix Composites," Journal of Materials Science, vol. 35, no. 2, pp. 411 - 418, Springer Verlag, Jan 2000.

The definitive version is available at https://doi.org/10.1023/A:1004715300441

Department(s)

Materials Science and Engineering

International Standard Serial Number (ISSN)

0022-2461

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2000 Springer Verlag, All rights reserved.

Publication Date

01 Jan 2000