Boron Carbide-Zirconium Boride In Situ Composites by the Reactive Pressureless Sintering of Boron Carbide-Zirconia Mixtures

• Published in: Journal of the American Ceramic Society Vol. 84; no. 3; pp. 642 - 644
• Main Authors: Goldstein, Adrian, Geffen, Ygal, Goldenberg, Ayala
• Format: Journal Article
• Language: English
• Published: Westerville, Ohio American Ceramics Society 01.03.2001; Blackwell; Wiley Subscription Services, Inc
• Subjects: Applied sciences; boron carbide; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Exact sciences and technology; sinter/sintering; Structural ceramics; Technical ceramics; zirconia: yttria-stabilized tetragonal polycrystal; Reaction sintering; Yttrium Oxides; Boron Carbides; Stabilized zirconia; Manufacturing; Experimental study; Composite material; Non oxide ceramics; Structural ceramic; Zirconium Borides
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1151-2916.2001.tb00714.x

The heating of B4C–YTZP (where YTZP denotes yttria‐stabilized zirconia polycrystals) mixtures, under an argon atmosphere, generates B4C–ZrB2 composites, because of a low‐temperature (<1500°C) carbide–oxide reaction. Composites derived from mixtures that include ≥15% YTZP are better sintered than monolithic B4C that has been fired under the same conditions. Firing to ∼2160°C (1 h dwell) generates specimens with a bulk density of ≥91% of the theoretical density (TD) for cases where the initial mixture includes ≥15% YTZP. Mixtures that include 30% YTZP allow a fired density of ≥97.5% TD to be attained. The behavior of the B4C–YTZP system is similar to that of the B4C–TiO2 system. Dense B4C–ZrB2 composites attain a hardness (Vickers) of 30–33 GPa.