Microstructure and high-temperature strength of textured and non-textured ZrB2 ceramics

Wen-Wen Wu; Yoshio Sakka; Mehdi Estili; Tohru S Suzuki; Toshiyuki Nishimura; Guo-Jun Zhang

doi:10.1088/1468-6996/15/1/014202

Microstructure and high-temperature strength of textured and non-textured ZrB₂ ceramics

Sci Technol Adv Mater. 2013 Dec 3;15(1):014202. doi: 10.1088/1468-6996/15/1/014202. eCollection 2014 Feb.

Authors

Wen-Wen Wu¹, Yoshio Sakka¹, Mehdi Estili², Tohru S Suzuki¹, Toshiyuki Nishimura³, Guo-Jun Zhang⁴

Affiliations

¹ Advanced Ceramics Group, National Institute for Materials Science (NIMS), 1-2-1 Tsukuba, Ibaraki, 305-0047, Japan.
² International Center for Young Scientists (ICYS), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, 305-0047, Japan.
³ Sialon Group, Sialon Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, 305-0044, Japan.
⁴ State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Shanghai, 200050, People's Republic of China.

Abstract

Zirconium diboride (ZrB₂) ceramic possesses a unique combination of nice mechanical performance, high melting point (> 3000 °C) and great high-temperature oxidation resistance (up to 1600 °C), which makes it a promising material system for ever-increasing ultra-high temperature (UHT) applications. However, ZrB₂ suffers from poor mechanical performance at UHTs, which could strongly limit its applications at UHT. Here, we successfully demonstrate that texturing is an effective strategy to greatly enhance the flexural strength of monolithic ZrB₂, reaching a high value of 810 ± 60 MPa at 1600 °C when loaded in c-axis direction. We thoroughly discuss the strengthening mechanism by in-depth microstructural observations and analysis. Our discovery has technological and scientific implications for other UHT ceramic systems, especially those using ZrB₂ as a matrix.

Keywords: High-temperature flexural strength; Microstructure; Texture; ZrB2.