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Showing 1 to 11 of 11 for “"UHTC"”.
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Advanced Synthesis of Ultra-High Temperature Ceramics (UHTCs) and High Temperature Electron Emitting Materials
… First, the ultra-high temperature ceramic (UHTC) zirconium diboride or ZrB2 was sintered by ultra-fast high temperature sintering (UHS). The UHS process was optimized and the sintering parameters for ZrB2 and other UHTCs were studied. ZrB2 is an ultra-high temperature ceramic (UHTC) with a …
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Active Measurement of a Micron-Order Gap Under High-Speed and High-Temperature Conditions
… properties, ultra-high-temperature ceramics (UHTCs) have risen as a promising solution to act as a protective barrier between the harsh environment and surface materials of these flight bodies. The mechanical operation of a portable hypersonic simulation device was developed in-house and …
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Investigating the Thermo-Mechanical Behavior of Highly Porous Ultra-High Temperature Ceramics using a Multiscale Quasi-Static Material Point Method
Ultra-high temperature ceramics (UHTCs) are a class of materials that maintain their structural integrity at high temperatures, e.g. 2000 °C. They have been limited in their aerospace applications because of their relatively high density and the difficulty involved in forming them into complex …
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Understanding How Tape Casting Titanium Diboride Shifts its Processing-Microstructure-Properties Paradigm Toward New Applications
The manufacturing of UHTC materials has significantly advanced over recent years, allowing for the development of new microstructures, architectures, shapes, and geometries to explore new properties and applications for these materials beyond aerospace. One of the UHTCs, titanium diboride (TiB2) …
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Processing to Enable Direct-Write Additive Manufacturing of Ceramics and Ceramic Composites
… (<335 >µm), ultra-high temperature ceramic (UHTC) monoliths. The final ZrB<sub>2</sub>-based paste exhibited an elastic shear modulus of ~10<sup>4</sup> Pa, flow index of 0.34, and flow stress of ~40 Pa, as-designed for monolithic printing. In discrete multi-material printing, dielectric and …
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Optimization of High Entropy Borides for Advanced Applications
… on the Ultra High Temperature Ceramic (UHTC) materials, based on transition metal borides and carbides, which are characterised by several advantageous physico-chemical properties, such as elevated melting temperatures, chemical inertness, good thermal and electrical conductivities, etc. …
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Aligned Continuous Cylindrical Pores Derived from Electrospun Polymer Fibers in Titanium Diboride
… thermal conductivity of candidate materials for UHTC applications at relevant temperatures using a finite difference model and a controlled sample environment. This low-cost processing technique facilitates the production of thermally and mechanically anisotropic structures into near-net shape …
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Fabricating Complex-Shaped Components by Room-Temperature Injection Molding of Aqueous Ceramic Suspension Gels
… an ultra-high temperature ceramic (UHTC) system.</p> <p>CeraSGels were highly loaded (>50 vol.%) with alumina powder and had a minimal amount (≤5 vol.%) of water-soluble polyvinylpyrrolidone (PVP). Rheological study of alumina CeraSGels using parallel plate rheometry revealed that …
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Microstructures and oxidation properties in hafnium-tantalum-nitride ceramics
Ultra high temperature ceramics (UHTC) comprise a class of materials characterized by high melting points, chemical inertness, high hardness, and moderate oxidation. These ceramics typically comprise either group IV or V metals bonded with boron, carbon or nitrogen. When in equal atomic ratio, a MX …
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Mechanical properties of boride based ceramics
<p>“This research focuses on the elevated mechanical properties of diboride based materials at room and elevated temperatures. These materials include a ZrB<sub>2</sub> ceramic, a ZrB<sub>2</sub>-WC-SiC ceramic, and a (Hf,Mo,Nb,Ta,W,Zr)B<sub>2</sub> high entropy boride (HEB). The room temperature …
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Colloidal Processing, Microstructural Evolution, and Anisotropic Properties of Textured Ultra-High Temperature Ceramics Prepared Using Weak Magnetic Fields
The texturing of ultra-high temperature ceramics (UHTCs) using weak magnetic fields is studied and developed for the first time. Textured UHTCs were prepared by magnetically assisted slip casting (MASC) in weak magnetic field (B ~ 0.5 T). Analytical calculations describing the balance of torques …