Strength and Young's modulus of silicon carbide layers of HTGR fuel particles at high temperatures

1991 ◽  
Vol 182 ◽  
pp. 6-10 ◽  
Author(s):  
Kazuo Minato ◽  
Kousaku Fukuda
Keyword(s):  
Silicon Carbide ◽  
Young’S Modulus ◽  
High Temperatures ◽  
Young's Modulus ◽  
Fuel Particles ◽  
Htgr Fuel

Control of stoichiometry, microstructure, and mechanical properties in SiC coatings produced by fluidized bed chemical vapor deposition

2008 ◽  
Vol 23 (6) ◽  
pp. 1785-1796 ◽  
Author(s):  
E. López-Honorato ◽  
P.J. Meadows ◽  
J. Tan ◽  
P. Xiao
Keyword(s):  
Mechanical Properties ◽  
Silicon Carbide ◽  
Chemical Vapor Deposition ◽  
Young’S Modulus ◽  
Fluidized Bed ◽  
Vapor Deposition ◽  
Young's Modulus ◽  
Chemical Vapor ◽  
Carbide Coatings ◽  
Fuel Particles

Stoichiometric silicon carbide coatings the same as those used in the formation of TRISO (TRistructural ISOtropic) fuel particles were produced by the decomposition of methyltrichlorosilane in hydrogen. Fluidized bed chemical vapor deposition at around 1500 °C, produced SiC with a Young’s modulus of 362 to 399 GPa. In this paper we demonstrate the deposition of stoichiometric silicon carbide coatings with refined microstructure (grain size between 0.4 and 0.8 μm) and enhanced mechanical properties (Young’s modulus of 448 GPa and hardness of 42 GPa) at 1300 °C by the addition of propene. The addition of ethyne, however, had little effect on the deposition of silicon carbide. The effect of deposition temperature and precursor concentration were correlated to changes in the type of molecules participating in the deposition mechanism.

Irradiation behavior of pyrolytic silicon carbide

1983 ◽  
Vol 41 ◽  
pp. 72-73
Author(s):  
R. J. Lauf
Keyword(s):  
Silicon Carbide ◽  
Fission Products ◽  
Thermodynamics And Kinetics ◽  
Neutron Fluences ◽  
Fuel Particles ◽  
Sic Coatings ◽  
Irradiation Behavior ◽  
Kinetics Of ◽  
Htgr Fuel

Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain a layer of pyrolytic silicon carbide to act as a miniature pressure vessel and primary fission product barrier. Optimization of the SiC with respect to fuel performance involves four areas of study: (a) characterization of as-deposited SiC coatings; (b) thermodynamics and kinetics of chemical reactions between SiC and fission products; (c) irradiation behavior of SiC in the absence of fission products; and (d) combined effects of irradiation and fission products. This paper reports the behavior of SiC deposited on inert microspheres and irradiated to fast neutron fluences typical of HTGR fuel at end-of-life.

Measurement of Young’s modulus and damping for hexoloy SG silicon carbide

1999 ◽  
Vol 41 (6) ◽  
pp. 611-615 ◽  
Author(s):  
A. Wolfenden ◽  
A.C. Anthony ◽  
M. Singh
Keyword(s):  
Silicon Carbide ◽  
Young’S Modulus ◽  
Young's Modulus

Micromechanical characterization of chemically vapor deposited ceramic films

1994 ◽  
Vol 9 (8) ◽  
pp. 2072-2078 ◽  
Author(s):  
J.M. Grow ◽  
R.A. Levy
Keyword(s):  
Silicon Carbide ◽  
Silicon Nitride ◽  
Boron Nitride ◽  
Silicon Dioxide ◽  
Boron Carbide ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Ceramic Films ◽  
Chemically Vapor Deposited ◽  
Micromechanical Characterization

In this study, nanoindentation is used to determine Young's modulus of chemically vapor deposited films consisting of silicon carbide, silicon nitride, boron carbide, boron nitride, and silicon dioxide. Diethylsilane and ditertiarybutylsilane were used as precursors in the synthesis of the silicon-based material, while triethylamine borane complex was used for the boron-based material. The modulus of these films was observed to be dependent on the processing conditions and resulting composition of the deposits. For the silicon carbide, silicon nitride, boron carbide, and boron nitride films, the carbon content in the films was observed to increase significantly with higher deposition temperatures, resulting in a corresponding decrease in values of Young's modulus. The composition of the silicon dioxide films was near stoichiometry over the investigated deposition temperature range (375–475 °C) with correspondingly small variations in the micromechanical properties. Subsequent annealing of these oxide films resulted in a significant increase in the values of Young's modulus due to hydrogen and moisture removal.

Effects of Aluminum Incorporation on the Young’s Modulus of 3C-SiC Epilayers

2019 ◽  
Vol 963 ◽  
pp. 305-308
Author(s):  
Jaweb Ben Messaoud ◽  
Jean François Michaud ◽  
Marcin Zielinski ◽  
Daniel Alquier
Keyword(s):  
Mechanical Properties ◽  
Silicon Carbide ◽  
Young’S Modulus ◽  
Stress Level ◽  
Microelectromechanical Systems ◽  
Young's Modulus ◽  
Al Doping ◽  
Noticeable Reduction

The silicon carbide cubic polytype (3C-SiC) is a material of choice to fabricate microelectromechanical systems. However, the mechanical properties of 3C-SiC-based devices are severely linked to the stress of the involved 3C-SiC material. Moreover, the stress level can hamper completing microsystems. As a consequence, in this study, we considered the influence of aluminum (Al) doping towards the mechanical properties of 3C-SiC epilayers and demonstrated a noticeable reduction of the Young’s modulus with a high Al incorporation.

Carbon monoxide-silicon carbide interaction in HTGR fuel particles

1991 ◽  
Vol 26 (9) ◽  
pp. 2379-2388 ◽  
Author(s):  
Kazuo Minato ◽  
Toru Ogawa ◽  
Satoru Kashimura ◽  
Kousaku Fukuda ◽  
Ishio Takahashi ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Silicon Carbide ◽  
Fuel Particles ◽  
Htgr Fuel

scholarly journals Amorphous Silicon Carbide Platform for Next Generation Penetrating Neural Interface Designs

Micromachines ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 480 ◽  
Author(s):  
Felix Deku ◽  
Christopher Frewin ◽  
Allison Stiller ◽  
Yarden Cohen ◽  
Saher Aqeel ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Amorphous Silicon ◽  
Young’S Modulus ◽  
Critical Thickness ◽  
Young's Modulus ◽  
Neural Interface ◽  
Cortical Tissue ◽  
Amorphous Silicon Carbide ◽  
Structural Support ◽  
Single Unit Recordings

Microelectrode arrays that consistently and reliably record and stimulate neural activity under conditions of chronic implantation have so far eluded the neural interface community due to failures attributed to both biotic and abiotic mechanisms. Arrays with transverse dimensions of 10 µm or below are thought to minimize the inflammatory response; however, the reduction of implant thickness also decreases buckling thresholds for materials with low Young’s modulus. While these issues have been overcome using stiffer, thicker materials as transport shuttles during implantation, the acute damage from the use of shuttles may generate many other biotic complications. Amorphous silicon carbide (a-SiC) provides excellent electrical insulation and a large Young’s modulus, allowing the fabrication of ultrasmall arrays with increased resistance to buckling. Prototype a-SiC intracortical implants were fabricated containing 8 - 16 single shanks which had critical thicknesses of either 4 µm or 6 µm. The 6 µm thick a-SiC shanks could penetrate rat cortex without an insertion aid. Single unit recordings from SIROF-coated arrays implanted without any structural support are presented. This work demonstrates that a-SiC can provide an excellent mechanical platform for devices that penetrate cortical tissue while maintaining a critical thickness less than 10 µm.

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