Production of UHTC Complex Shapes and Architectures

In spite of the difficult sinterability of Zr and Hf borides and carbides, recent results highlight that these ceramics can be produced with full density, fine microstructure, and controlled mechanical and thermal properties, through different procedures: pressureless sintering and hot pressing with proper sintering aids, reactive synthesis/sintering procedures starting from precursors, and field assisted technologies like spark plasma sintering. More recently, the use of near net shaping techniques and the development of UHTC porous components open the way to further and innovative applications, where the performances, fixed the material, are linked to 2D or 3D architectures and the high ratio of specific surface area to volume of the component and to the features of the porosity itself. Structural lightweight parts, insulator panels, filters, radiant burners, and solar absorbers are some of the possible applications.