Download file (5.89 MB)
Download as zip (5.8 MB)

Collection

Citation

Description:

Grain boundaries, twins, and defects are considered to influence the thermomechanical behavior of any covalent ceramic. As a result, monolithic B4C samples show different shapes, and the present theoretical models fail to fit them over the entire temperature range. We fabricated a novel high-density boron carbide to overcome these issues and evaluated its high-temperature bending strength. The as-obtained ceramic comprises boron carbide grains and a fine grain-boundary metal Pt framework. The material shows a decreased strength, which is due to a non-linear increase in the volume expansion coefficient of the B4C.
Recovery in strength above 1000 ℃ is due to the presence of twins, their growth, and rearrangements. We consider twin rearrangements evidence for a novel ‘micro’ mechanism of high-temperature stress accommodation for the boron carbide bulks.

Rights:

• Creative Commons BY-NC-ND Attribution-NonCommercial-NoDerivs 4.0 International
  

  © 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/

Keyword: boron carbide, Pt framework, Modified grain boundaries, Spark plasma sintering, Bending strength, Asymmetric twins

Date published: 2019-12-20

Publisher: Elsevier BV

Journal:

• Ceramics International (ISSN: 02728842) vol. 46 issue. 7 p. 9136-9144

Funding:

• World Premier International Research Center Initiative (WPI), MEXT, Japan

Manuscript type: Author's version (Accepted manuscript)

MDR DOI: https://doi.org/10.48505/nims.4986

First published URL: https://doi.org/10.1016/j.ceramint.2019.12.163

Related item:

Other identifier(s):

Contact agent:

Updated at: 2024-11-19 16:30:25 +0900

Published on MDR: 2024-11-19 16:30:25 +0900