Ultra High Temperature Ceramics

Abstract

Most engineering applications concerned with exposure to extremely high temperatures, (>2000°C), and harsh environmental conditions require the use of ceramic materials possessing melting points in excess of ~ 3000°C. Such ceramics, more commonly referred to as ultra high temperature ceramics (UHTCs), are required to possess a desired combination of mechanical and physical properties, which are retained despite the extremely high temperatures as demanded by their applications. However, there are some drawbacks of such materials, with respect to both their processing as well as their properties, which limit their applications to a considerable extent and demand careful engineering of their composition and microstructure to circumvent those limitations. Continuing research efforts have been focused on addressing such issues. Against this backdrop, the present review summarizes the various properties possessed by the UHTCs and critically analyzes the issues concerned with such materials. Through such analysis, an overview of the more recent research efforts that have been conducted to solve the various issues related to this material class is presented. This also highlights the difficulties associated with experimental assessments of the various properties of such materials. Lastly, the various existing applications and potential future applications for such materials are mentioned, with an outlook towards the issues that need to be addressed in the near future.