ZrB2/HfB2–SiC Ceramics Modified by Refractory Carbides: An Overview

Resumo

The literature on the manufacture and characterization of ZrB₂/HfB₂–SiC ultra-high temperature ceramics (UHTCs) modified by ultra-refractory carbides (ZrC, HfC, B₄C, TaC, VC, and WC) was analyzed. The specifics of various consolidation techniques are considered in the context of properties of the prepared samples. The role of these modifiers in the fabrication of UHTCs with improved characteristics was found to consist in grain growth inhibition and in scavenging oxide impurities, primarily ZrO₂/HfO₂, from the surfaces of metal diboride and silicon carbide particles. The role of additives on the oxidation resistance of the manufactured materials is discussed.