Polyimide as carbon and ceramic polysilazane precursors to obtain high carbon content ceramic for high-temperature applications

2020 ◽  
Author(s):  
André V. B. Andrade ◽  
Luiz F. Belchior Ribeiro ◽  
Emanoelle Diz Acosta ◽  
Fernando J. Da Costa ◽  
Maíra D. Mallmann ◽  
...  
Keyword(s):  
High Temperature ◽  
Carbon Content ◽  
High Carbon ◽  
High Carbon Content ◽  
Temperature Applications

Tailoring Carbon Nanoclusters to Desired Morphologies

1998 ◽  
Vol 13 (9) ◽  
pp. 2438-2444 ◽  
Author(s):  
Jun Jiao ◽  
Supapan Seraphin
Keyword(s):  
Carbon Monoxide ◽  
High Temperature ◽  
Carbon Content ◽  
Arc Discharge ◽  
Low Carbon ◽  
High Carbon ◽  
High Carbon Content ◽  
Carbon Nanoclusters ◽  
Comparative Manner

The preparation and structural characterization of carbon nanoclusters of different morphologies produced by three different methods and under a variety of conditions is reported. In a comparative manner, the growth phenomena and structural properties of carbon nanoclusters are investigated as synthesized by (a) the high temperature (˜3000 °C) and high carbon-content process of the conventional arc-discharge, (b) the high temperature but low carbon-content process of the modified arc-discharge, and finally (c) the relatively low temperature (˜500 °C) process of Ni catalytic disproportionation of carbon monoxide.

scholarly journals Physical and chemical processes in the cavity of the oxygen converter when burning the bath with the afterburning of exhaust gases

2019 ◽  
pp. 116-128
Author(s):  
A.G. Chernyatevich ◽  
L.S. Molchanov ◽  
V.V. Vakulchuk ◽  
B.Y. Yushkevich
Keyword(s):  
High Temperature ◽  
Carbon Content ◽  
Oxygen Converter ◽  
Slag Formation ◽  
High Carbon ◽  
High Carbon Content ◽  
Double Row ◽  
Exhaust Gases ◽  
Converter Bath ◽  
Temperature Modeling

The aim of the study is to study the characteristics of physicochemical processes in the cavity of an oxygen converter when purging a bath through two-tier tuyeres of various designs. The analysis showed that the classical designs of oxygen tuyeres equipped with tips with Laval nozzles do not always satisfy the requirements of the technology. The article presents the results of laboratory high-temperature modeling of the process of purging the converter bath through two-tier tuyeres equipped with tips of various designs. The studies were carried out on a multipurpose installation mounted on the basis of a 150-kg induction furnace and a 60-kg converter manufactured at a scale of 1:18 relative to 160 tons of an industrial unit. It is shown that the use of a two-tier lance provides additional advantages for the smelting process. So, in the initial and main periods of purging the converter bath through a two-tier lance with a double-row tip, it was possible to accelerate the process of slag formation without the addition of fluorspar, to intensify the removal of phosphorus at a high carbon content. Upon completion of the initial purge period at a low metal temperature of 1300-1330 ° C and the corresponding basicity of liquid slag, the degree of dephosphorization of 73.3-79.1% is achieved. When used for blowing two-tier tuyeres with double-row tips, the efficiency of afterburning of CO exhaust gases to CO2 also increases at the same decarburization rate of the bath. Based on the data of high-temperature modeling, the rational design of the two-tier lance has been determined, which ensures: balance of the heat balance; yield increase; creating conditions for the removal of phosphorus at a high carbon content; exclusion of negative effects on the lining.

ALGOMA AR225

Alloy Digest ◽  
2003 ◽  
Vol 52 (12) ◽  
Keyword(s):  
Carbon Steel ◽  
Chemical Analysis ◽  
Physical Properties ◽  
Carbon Content ◽  
Brinell Hardness ◽  
Low Cost ◽  
Heat Treating ◽  
Rolled Plate ◽  
High Carbon ◽  
High Carbon Content

Abstract Algoma AR225 is a carbon steel developed primarily to supply a low-cost material for high-abrasion applications. It is furnished in the form of as-rolled plate with a relatively high carbon content (0.35-0.45%). AR-225 is sold on the basis of chemical analysis only; the number 225 signifies the approximate Brinell hardness. On thicknesses one-half inch and over, this Brinell value may be lower than 225 because of higher finishing temperatures. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, machining, and joining. Filing Code: CS-138. Producer or source: Algoma Steel Corporation Ltd.

Effects of Carbon Concentration Upon Oxygen Precipitation in Cz Si

1987 ◽  
Vol 104 ◽  
Author(s):  
S. Hahn ◽  
M. Arst ◽  
K. N. Ritz ◽  
S. Shatas ◽  
H. J. Stein ◽  
...  
Keyword(s):  
Carbon Content ◽  
Carbon Concentration ◽  
High Carbon ◽  
High Carbon Content ◽  
Oxygen Precipitation ◽  
Oxygen Precipitate ◽  
High Carbon Concentration ◽  
Precipitation Characteristics ◽  
C Complex ◽  
Oxide Precipitate

ABSTRACTEffects of high carbon concentration upon oxygen precipitate formation in Cz silicon have been investigated by combining various furnace and rapid thermal annneals. Even though oxide precipitate density increases with increasing carbon levels, Cs, synchrotron radiation section topographs of processed high carbon content wafers (Cs ∼ 4ppma) exhibit Pendellosung fringes, indicating a strain free bulk state. Our optical microscopic data have also shown very few defect etch features inside the bulk. A model based upon a direct coupling of both SiO2 and Si-C complex formation reactions is used to explain rather unique oxygen precipitation characteristics in the high carbon content Cz Si materials.

Synthesis of high carbon content microspheres using 2-step microwave carbonization, and the influence of nitrogen doping on catalytic activity

Carbon ◽  
2013 ◽  
Vol 60 ◽  
pp. 307-316 ◽  
Author(s):  
Alum Jung ◽  
Suenghoon Han ◽  
Teawon Kim ◽  
Won Joon Cho ◽  
Kun-Hong Lee
Keyword(s):  
Catalytic Activity ◽  
Carbon Content ◽  
Nitrogen Doping ◽  
High Carbon ◽  
High Carbon Content

Assessment of the Fitness for Service of the Flamanville EPR Reactor Pressure Vessel Closure Head and Bottom Head Domes Containing a Segregation Zone Characterized by a High Carbon Content

2018 ◽  
Author(s):  
Isabelle Delvallée-Nunio ◽  
Olivier Loiseau ◽  
Daniel Monhardt ◽  
Audrey Buiron ◽  
Franck Dubois
Keyword(s):  
Fracture Toughness ◽  
Carbon Content ◽  
Charpy Impact ◽  
Fracture Analysis ◽  
Material Testing ◽  
Charpy Impact Energy ◽  
High Carbon ◽  
High Carbon Content ◽  
Segregation Zone ◽  
Positive Segregation

To complete the manufacturing process qualification of the closure head and bottom head domes of the Flamanville EPR RPV in 16MND5 ferritic steel (similar to A508 cl3), AREVA NP performed in 2014 material testing on a sacrificial dome so-called UA Sup. These tests revealed that the Charpy impact energy at 0°C — in the positive segregation zone at ¼ thickness — was lower than 60 J, the minimum value required by the French regulation. Thereafter, this result was explained by the high carbon content close to 0.3 % — against 0.18 % in the ladle — due to the forging process. The positive segregation was insufficiently eliminated to avoid high carbon content in certain location. As the level of Charpy impact energy is an indicator of the level of fracture toughness, a thorough material characterization of the segregation zone, as well as a brittle fracture analysis have been proposed and carried out by AREVA NP to demonstrate that the Flamanville EPR RPV domes are tough enough for a safe operation. The principles of the demonstration approach were reviewed by ASN and IRSN in 2015 and the final safety case was submitted to the ASN and IRSN review in December 2016. The latter led to the conclusion that, even if the segregation zone fracture toughness is lowered in comparison to that of the acceptance test zone, this does not put into question the Flamanville EPR RPV fitness for service as long as adequate in-service inspection of the domes is periodically performed. This paper aims at presenting the key elements of the IRSN assessment from part of which this conclusion was drawn, namely the material testing program, the description of the loadings in normal and accidental conditions, and the brittle fracture analysis.

Study of TiC Interaction and its Reaction Products with the Different Carbon Content Steels

2020 ◽  
Vol 975 ◽  
pp. 59-64
Author(s):  
Andrey N. Anikeev ◽  
Ilia V. Chumanov ◽  
Vadim Sedukhin
Keyword(s):  
High Temperature ◽  
Carbon Steel ◽  
Titanium Carbide ◽  
Carbon Content ◽  
Thermodynamic Modeling ◽  
High Carbon Steel ◽  
Reaction Products ◽  
High Carbon ◽  
Scanning Microscope ◽  
Interaction Processes

Study of TiC interaction with low-and high-carbon steel is presented in this article. Was carried out interaction thermodynamic modeling in the temperature range of 900-1800 °C, which showed that titanium carbide would dissolve in melts with these compositions, regardless of melt’s carbon content at given parameters. The obtained thermodynamic results were verified by conducting an experiment with high-temperature complex in order to study substances interaction processes. The obtained experimental samples were studied with scanning microscope as well as structure and compounds composition, obtained as a result of experiment mentioned above.

Sign in / Sign up

Export Citation Format

Share Document