Mechanical Behavior of Zirconium Diboride-Silicon Carbide-Boron Carbide Ceramics up to 2200 ⁰C
The mechanical properties of hot pressed zirconium diboride-silicon carbide-boron carbide (ZrB2-SiC-B4C) ceramics were characterized from room temperature up to 2200⁰C in an argon atmosphere. The average ZrB2 grain size was 3.0μm. The SiC particles segregated into clusters, and the largest clusters were >30μm in diameter. The room temperature flexural strength was 700MPa, decreasing to 540MPa at 1800⁰C and to 260MPa at 2200⁰C. The strength was controlled by the SiC cluster size up to 1800⁰C. At higher temperatures, strength was controlled by formation of liquid phases, and precipitation of large BN and B-O-C-N inclusions. The mechanical behavior of these materials changes at~1800⁰C, meaning that extrapolation of properties from lower temperatures is not accurate. Mechanical behavior in the ultra-high temperature regime was dominated by impurities and changes in microstructure. Therefore, the use of higher purity materials could lead to significant improvements in ultra-high temperature strength.
E. W. Neuman et al., "Mechanical Behavior of Zirconium Diboride-Silicon Carbide-Boron Carbide Ceramics up to 2200 ⁰C," Journal of the European Ceramic Society, vol. 35, no. 2, pp. 463-476, Elsevier Ltd, Feb 2015.
The definitive version is available at http://dx.doi.org/10.1016/j.jeurceramsoc.2014.09.021
Materials Science and Engineering
Keywords and Phrases
Failure analysis; Mechanical properties; Silicon carbide; Ultra-high temperature ceramics; Zirconium diboride; Boron carbide ceramics; Mechanical behavior
International Standard Serial Number (ISSN)
Article - Journal
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