Tantalum Carbides

Tantalum carbides comprise a class of ultrahigh temperature ceramics with the monocarbide TaC phase having a melting temperature approaching 4000°C, which is one of the highest known values. These particular carbides, along with others in the Group V transition metals, exhibit a range of microstructures and mechanical properties. In this chapter, a literature review of the interrelationship of phases, microstructure morphologies, and mechanical properties are discussed. The influence of phase transformation mechanisms is developed in terms of the C/Ta ratio and how transformation pathways regulate the microstructures. Tantalum carbides' mechanical properties including fracture toughness, hardness, and elevated temperature plasticity with their associated dislocation mechanisms are reviewed yielding an understanding of the metallic-like and ceramic-like mechanical responses noted to occur in these materials. The survey of microstructure and mechanical attributes highlights the exciting opportunities available to these carbides for tailoring structural loading.