High-toughness zeta-phase carbides

Abstract

A ceramic material having a high toughness can include carbon and a transition metal. The transition metal can have an elemental body centered cubic structure at room temperature. A substantial amount of the ceramic can be of a rhombohedral ζ phase of the transition metal and carbon. These materials can have a high thermal shock resistance, high fracture toughness, and good high temperature performance. A particulate mixture of a carbon source and a transition metal source can be assembled () and reacted () under high pressure and high temperature. The transition metal source can include a transition metal of a metal which has an elemental BCC structure at room temperature. The particulate mixture carbon to transition metal ratio is chosen so as to achieve a zeta phase carbide and processing is affected in order to retain the zeta phase at a substantial weight percent of the material (i.e. greater than about 5 wt %). The carbide ceramic can be cooled () and depressurized () to acquire the ceramic material.