Fabrication of Energy-Saving Mgo with Large Grain Size and Low Thermal Conductivity: Towards a New Type of Magnesia for High-Temperature Furnaces

2021 ◽  
Author(s):  
Xinming Ren ◽  
Beiyue Ma
Keyword(s):  
Thermal Conductivity ◽  
Grain Size ◽  
High Temperature ◽  
Energy Saving ◽  
Low Thermal Conductivity ◽  
New Type ◽  
High Temperature Furnaces

La2O3 Doped Y2O3 Stabilized ZrO2 TBC Prepared by EB-PVD

2006 ◽  
Vol 317-318 ◽  
pp. 501-504 ◽  
Author(s):  
Mineaki Matsumoto ◽  
Norio Yamaguchi ◽  
Hideaki Matsubara
Keyword(s):  
Thermal Conductivity ◽  
High Temperature ◽  
High Resistance ◽  
Thermal Transport ◽  
Temperature Stability ◽  
High Temperature Stability ◽  
Microstructural Observation ◽  
Low Thermal Conductivity ◽  
Ysz Coating

Effect of La2O3 addition on thermal conductivity and high temperature stability of YSZ coating produced by EB-PVD was investigated. La2O3 was selected as an additive because it had a significant effect on suppressing densification of YSZ. The developed coating showed extremely low thermal conductivity as well as high resistance to sintering. Microstructural observation revealed that the coating had fine feather-like subcolumns and nanopores, which contributed to limit thermal transport. These nanostructures were thought to be formed by suppressing densification during deposition.

Layered tellurides: stacking faults induce low thermal conductivity in the new In2Ge2Te6 and thermoelectric properties of related compounds

2017 ◽  
Vol 5 (36) ◽  
pp. 19406-19415 ◽  
Author(s):  
Robin Lefèvre ◽  
David Berthebaud ◽  
Oleg Lebedev ◽  
Olivier Pérez ◽  
Célia Castro ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
High Temperature ◽  
Thermoelectric Properties ◽  
Stacking Faults ◽  
Layered Compound ◽  
Low Thermal Conductivity ◽  
Related Compounds

A new ternary layered compound In2Ge2Te6, belonging to the hexatellurogermanate family has been synthesized from the reaction of appropriate amounts of the pure elements at high temperature in sealed silica tubes.

Study and Application of Plastic Construction Materials

2011 ◽  
Vol 99-100 ◽  
pp. 1117-1120 ◽  
Author(s):  
Mao Quan Xue
Keyword(s):  
Thermal Conductivity ◽  
Corrosion Resistance ◽  
Energy Saving ◽  
Thermal Insulation ◽  
Flame Retardancy ◽  
Building Materials ◽  
Construction Materials ◽  
Low Thermal Conductivity ◽  
Building Walls

As new building materials, plastic has light weigh, corrosion resistance, low thermal conductivity, thermal insulation, waterproof, energy-saving, molding convenient, high recycling characteristic, widely used in building materials. According to the research of improving its flame retardancy, strength, thermal insulation, waterproof properties, the application of plastic use in doors and windows, pipeline, building walls and roofs of buildings, etc. were reviewed, and the developing direction was discussed.

scholarly journals High-entropy (Nd0.2Sm0.2Eu0.2Y0.2Yb0.2)4Al2O9 with good high temperature stability, low thermal conductivity and anisotropic thermal expansivity

2020 ◽  
Author(s):  
Zifan Zhao ◽  
Huimin Xiang ◽  
Heng Chen ◽  
Fu-zhi Dai ◽  
Xiaohui Wang ◽  
...  
Keyword(s):  
Phase Transition ◽  
Thermal Conductivity ◽  
Thermal Expansion ◽  
Rare Earth ◽  
High Temperature ◽  
Phase Stability ◽  
Temperature Phase ◽  
Low Thermal Conductivity ◽  
High Entropy ◽  
Anisotropic Thermal Expansion

Abstract The critical requirements for the environmental barrier coating (EBC) materials of silicon-based ceramic matrix composites (CMCs) including good tolerance to harsh environments, thermal expansion match with the interlayer mullite, good high-temperature phase stability and low thermal conductivity. Cuspidine-structured rare-earth aluminates RE4Al2O9 have been considered as candidates of EBCs for their superior mechanical and thermal properties, but the phase transition at high temperatures is a notable drawback of these materials. To suppress the phase transition and improve the phase stability, a novel cuspidine-structured rare-earth aluminate solid solution (Nd0.2Sm0.2Eu0.2Y0.2Yb0.2)4Al2O9 was designed and successfully synthesized inspired by entropy stabilization effect of high entropy ceramics. The as-synthesized (Nd0.2Sm0.2Eu0.2Y0.2Yb0.2)4Al2O9 exhibits close thermal expansion coefficient (6.96×10-6 /K at 300-1473 K) to that of mullite, good phase stability from 300 K to 1473 K, and low thermal conductivity (1.50 W·m-1·K-1 at room temperature). In addition, strong anisotropic thermal expansion has been observed compared to Y4Al2O9 and Yb4Al2O9. The mechanism for low thermal conductivity is attributed to the lattice distortion and mass difference of the constituent atoms while the anisotropic thermal expansion is due to the anisotropic chemical bonding enhanced by the large size rare earth cations.

Sn20.5□3.5As22I8: A Largely Disordered Cationic Clathrate with a New Type of Superstructure and Abnormally Low Thermal Conductivity

2007 ◽  
Vol 13 (18) ◽  
pp. 5090-5099 ◽  
Author(s):  
Julia V. Zaikina ◽  
Kirill A. Kovnir ◽  
Alexei V. Sobolev ◽  
Igor A. Presniakov ◽  
Yuri Prots ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Low Thermal Conductivity ◽  
New Type

Inorganic Insulated Metal Substrates

2015 ◽  
Vol 2015 (HiTEN) ◽  
pp. 000219-000226
Author(s):  
Pavel Shashkov ◽  
Steven Curtis ◽  
Giles Humpston
Keyword(s):  
Thermal Conductivity ◽  
Grain Size ◽  
High Temperature ◽  
Critical Role ◽  
Cost Effective ◽  
High Thermal Conductivity ◽  
Ceramic Surface ◽  
Metal Base ◽  
Dielectric Thickness ◽  
Metal Substrates

Insulated metal substrates (IMS) are gaining ground in electronics applications thanks to their high thermal conductivity and low cost. However, the organic dielectrics (such as epoxy or polyimide based material) traditionally used on IMS are limited by their maximum operating temperature, generally to below 150–200 °C. Thus in high temperature applications manufacturers are restricted to using expensive inorganic substrates such as alumina (Al2O3), aluminium nitride (AlN) or silicon nitride (Si3N4). A cost-effective IMS with an inorganic dielectric would be an attractive alternative for high temperature electronics. Cambridge Nanotherm has developed an electrochemical process for building inorganic dielectric ceramic onto a metal base. Nanotherm ceramic material is nanocrystalline alumina with a grain size of 20 to 60 nanometres. This grain size plays a critical role in providing the dielectric layer with its unique combination of properties such as high thermal conductivity (6–7 W/mK), high dielectric strength (>50 V/um) and formability when applied on thin, foil-type substrates. The Nanoceramic layer can be built from 3 to 50 microns thick, depending on the breakdown voltage required. This avoids excessive dielectric thickness that unnecessarily increases the thermal resistance of the system. The electric circuit is built onto the ceramic surface using either PVD metal sputtering followed by galvanic metal build up or conventional thick film processing. The result is a cost-effective, easy to process and use inorganic substrate with a thermal conductivity around 150 W/mK and a maximum working temperature above 350 °C. This paper will present an overview of the key electrical and thermal properties of Nanoceramic aluminium substrates and their manufacturing process. Potential use in the thermal management of high temperature electronic devices will be discussed with reference to some applications.

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