Thermal Spraying of Ultra-High Temperature Ceramics: A Review on Processing Routes and Performance

Abstract

Ultra-high temperature ceramics (UHTCs) are materials defined as having melting points over 3000 °C and withstand temperatures beyond 2000 °C without losing functionality. As service environments become even more extreme, such materials will be needed for the next generation of aeronautic vehicles. Whether it is atmospheric re-entry or sustained hypersonic flight, materials with resistance to extreme temperature will be in demand. Due to the size and shape limitations encountered by current processing methods of bulk UHTCs research of UHTC coatings, specifically thermal spray UHTC coatings, is accelerating. This paper first presents a general summary of UHTC properties, followed by a comprehensive summary of the processing routes and microstructures of current UHTC thermal spray coatings. Then, a detailed review of the oxidation and ablation resistance of UHTC thermal spray coatings is outlined. Finally, potential avenues for the development of new UHTC coating compositions are explored.

Design and CFD Analysis on the Reduction of Thermal Effect in Re-entry Vehicle by Using Retractable Aerospike

“…UHTC coatings can be used to solve this problem. As C-and SiC-based composites become more widely used as structural components in aeronautics, protective coatings will be required to protect them from the harshest environments [31].…”

Ultrafine ZrB2 Ceramic Powders Prepared by a Sol–Gel Method Synergized with a Carbothermic Reaction and Their Improved Sintering Performance

“…Ultrahigh-temperature ceramics (UHTCs) are the most promising candidates for the fabrication of thermal protective composites due to their extremely high melting point and high temperature stability. − Typically, UHTCs include transition-metal carbides and borides, such as TiC, HfC, TaB 2 , ZrB 2 , and HfB 2 . − Among them, ZrB 2 UHTCs, with outstanding physicochemical properties, such as a high melting point (>3000 °C), high hardness, and good thermal shock resistance, have been widely investigated for applications under extreme conditions. − However, the practical applications of the ZrB 2 UHTCs are largely hindered by poor ablation resistance and high fragility, due to their low density and large grain size. Against this background, many efforts have been devoted to improving the sintering activity as well as the mechanical properties of ZrB 2 UHTCs by controlling the quality of the ZrB 2 powders via various preparation strategies.…”

Environmental conical nozzle levitator equipped with dual wavelength lasers

“…The future of many aspects of technology will require new ultra-high temperature ceramics (UHTCs): materials with operating temperatures above 2273 K. 1,2 Travel within our solar system will require next-generation heat shields that can withstand both high temperatures and highly reactive environments. For example, re-entry temperatures on Mars and Venus are estimated to be ∼1573 K 3 and ∼3023 K 4 respectively; atmosphere will add to the burden of the heat shield materials.…”

“…The future of many aspects of technology will require new ultra‐high temperature ceramics (UHTCs): materials with operating temperatures above 2273 K 1,2 . Travel within our solar system will require next‐generation heat shields that can withstand both high temperatures and highly reactive environments.…”