Ultra High Temperature Ceramics

Ultra High Temperature Ceramics

Ultra High Temperature Ceramics

The first comprehensive book to focus on ultra-hightemperature ceramic materials in more than 20 years Ultra-High Temperature Ceramics are a family of compounds thatdisplay an unusual combination of properties, including extremelyhigh melting temperatures (>3000°C), high hardness, andgood chemical stability and strength at high temperatures. Typical UHTC materials are the carbides, nitrides, and borides oftransition metals, but the Group IV compounds (Ti, Zr, Hf) plus TaCare generally considered to be the main focus of research due tothe superior melting temperatures and stable high-meltingtemperature oxide that forms in situ. Rather than focusing on thelatest scientific results, Ultra-High Temperature Ceramics:Materials for Extreme Environment Applications broadly andcritically combines the historical aspects and the state-of-the-arton the processing, densification, properties, and performance ofboride and carbide ceramics. In reviewing the historic studies and recent progress in thefield, Ultra-High Temperature Ceramics: Materials for ExtremeEnvironment Applications provides: Original reviews of researchconducted in the 1960s and 70s Content on electronic structure,synthesis, powder processing, densification, property measurement,and characterization of boride and carbide ceramics. Emphasis on materials for hypersonicaerospace applications such as wing leading edges and propulsioncomponents for vehicles traveling faster than Mach 5 Information on materials used in theextreme environments associated with high speed cutting tools andnuclear power generation Contributions are based on presentations by leading researchgroups at the conference "Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications II" held May 13-19,2012 in Hernstein, Austria. Bringing together disparate researchersfrom academia, government, and industry in a singular forum, themeeting cultivated didactic discussions and efforts between benchresearchers, designers and engineers in assaying results in abroader context and moving the technology forward toward near- andlong-term use. This book is useful for furnace manufacturers,aerospace manufacturers that may be pursuing hypersonic technology,researchers studying any aspect of boride and carbide ceramics, andpractitioners of high-temperature structural ceramics.

Boron Rich Solids

Boron Rich Solids

Boron Rich Solids

The objective of this book is to discuss the current status of research and development of boron-rich solids as sensors, ultra-high temperature ceramics, thermoelectrics, and armor. Novel biological and chemical sensors made of stiff and light-weight boron-rich solids are very exciting and efficient for applications in medical diagnoses, environmental surveillance and the detection of pathogen and biological/chemical terrorism agents. Ultra-high temperature ceramic composites exhibit excellent oxidation and corrosion resistance for hypersonic vehicle applications. Boron-rich solids are also promising candidates for high-temperature thermoelectric conversion. Armor is another very important application of boron-rich solids, since most of them exhibit very high hardness, which makes them perfect candidates with high resistance to ballistic impact. The following topical areas are presented: •Boron-rich solids: science and technology •Synthesis and sintering strategies of boron rich solids •Microcantilever sensors •Screening of the possible boron-based thermoelectric conversion materials; •Ultra-high temperature ZrB2 and HfB2 based composites •Magnetic, transport and high-pressure properties of boron-rich solids •Restrictions of the sensor dimensions for chemical detection •Armor

Ultra High Temperature Materials II

Ultra High Temperature Materials II

Ultra High Temperature Materials II

This exhaustive work in three volumes and over 1300 pages provides a thorough treatment of ultra-high temperature materials with melting points over 2500 °C. The first volume focuses on Carbon and Refractory Metals, whilst the second and third are dedicated solely to Refractory compounds and the third to Refractory Alloys and Composites respectively. Topics included are physical (crystallographic, thermodynamic, thermo physical, electrical, optical, physico-mechanical, nuclear) and chemical (solid-state diffusion, interaction with chemical elements and compounds, interaction with gases, vapours and aqueous solutions) properties of the individual physico-chemical phases of carbon (graphite/graphene), refractory metals (W, Re, Os, Ta, Mo, Nb, Ir) and compounds (oxides, nitrides, carbides, borides, silicides) with melting points in this range. It will be of interest to researchers, engineers, postgraduate, graduate and undergraduate students alike. The reader is provided with the full qualitative and quantitative assessment for the materials, which could be applied in various engineering devices and environmental conditions at ultra-high temperatures, on the basis of the latest updates in the field of physics, chemistry, materials science and engineering.

MAX Phases and Ultra High Temperature Ceramics for Extreme Environments

MAX Phases and Ultra High Temperature Ceramics for Extreme Environments

MAX Phases and Ultra High Temperature Ceramics for Extreme Environments

Ceramics are a versatile material, more so than is widely known. They are thermal resistant, poor electrical conductors, insulators against nuclear radiation, and not easily damaged, making ceramics a key component in many industrial processes. MAX Phases and Ultra-High Temperature Ceramics for Extreme Environments investigates a new class of ultra-durable ceramic materials, which exhibit characteristics of both ceramics and metals. Readers will explore recent advances in the manufacturing of ceramic materials that improve their durability and other physical properties, enhancing their overall usability and cost-effectiveness. This book will be of primary use to researchers, academics, and practitioners in chemical, mechanical, and electrical engineering. This book is part of the Research Essentials collection.

Low Temperature Low Pressure Fabrication of Ultra High Temperature Ceramics UHTCs

Low Temperature  Low Pressure Fabrication of Ultra High Temperature Ceramics  UHTCs

Low Temperature Low Pressure Fabrication of Ultra High Temperature Ceramics UHTCs

The US Air Force is interested in developing fiber-reinforced ceramic composites that perform at ultra-high temperatures (greater or more than 1500 degrees C) under oxidative conditions, especially for hypersonic vehicles. Two potential approaches are: (a) Utilizing existing carbon-fiber-reinforced carbon-matrix composites (C/C) or carbon-fiber-reinforced silicon carbide-matrix composites (C/SiC) coated by thick (>100 um) ultra-high temperature ceramic (UHTC) coatings, or (b) Replacing the C and SiC matrices of such composites with an ultra-high temperature matrix, processed by conventional composite techniques. The most investigated UHTCs are ZrB2/SiC and HfB2/SiC particulate composites (70:30 to 80:20 volume ratio). Wet processing via slurries is potentially a practical method for making such thick coatings and matrices. The project focused on developing slurry processing for thick ZrB2/SiC coatings on SiC and, to a limited extent, C/SiC composite substrates using preceramic and precarbon polymers combined with inert fillers and/or reactive metals. The evolved coatings were tested for their oxidation resistance under various conditions. A limited effort to assess the capability of bulk compositions made of slurries suitable for processing matrices for fiber-reinforced composites was also performed. Out of two distinctly different approaches and various compositions and preceramic polymers, the most promising stepwise approach was determined to be (1) forming ZrB2/C porous coatings ("preforms") processed from phenolic-based slurries, then (2) reacting the preform coatings with molten Si to form SiC and (3) converting residual Si to SiC. This technique resulted in highly dense, well adhering composite coatings that were 100 um thick and over. Thick coatings made by this approach provided much better characteristics and performance than other formulations and processes.

MAX Phases and Ultra high Temperature Ceramics for Extreme Environments

MAX Phases and Ultra high Temperature Ceramics for Extreme Environments

MAX Phases and Ultra high Temperature Ceramics for Extreme Environments

"This book investigates a new class of ultra-durable ceramic materials, which exhibit characteristics of both ceramics and metals, and will explore recent advances in the manufacturing of ceramic materials that improve their durability and other physical properties, enhancing their overall usability and cost-effectiveness"--

Reaction Processing for the Development of Ultra high Temperature Ceramics

Reaction Processing for the Development of Ultra high Temperature Ceramics

Reaction Processing for the Development of Ultra high Temperature Ceramics

"Research into ultra high temperature materials has increased in recent years due to the need for material systems that can withstand the temperatures associated with hypersonic flight applications. ZrB2 and HfB2 are among the candidates for these extreme conditions. These diborides have melting temperatures that exceed 3000°C, the potential for strength retention at elevated temperatures, and moderate oxidation resistance when compared to high temperature carbides. However, diborides have often been reported to exhibit low strength and significant strength degradation by 1500°C; therefore, limiting their use at high temperatures ... This research focused on processing zirconium diboride (ZrB2) ceramics that exhibit improved mechanical performance and reduced impurity content. Three processing methods have been used to produce dense ZrB2 ceramics; conventional hot pressing, reactive hot pressing, and pressureless sintering"--Abstract, leaf iv.