Belite Cement Prepared from High Carbon-Content Fly Ash

2016 ◽  
Vol 866 ◽  
pp. 20-24
Author(s):  
Yuan Yuan Wan ◽  
Yong Hao Fang

Stockpiled high carbon-content fly ash and lime was used to prepare belite cement by hydrothermal reaction followed by low temperature calcination. Sodium hydroxide was added as an activator to accelerating the reaction. 0-1.5 wt% Na2O equivalent NaOH was added as a aqueous solution into the mixture of 20 wt%-35 wt% CaO and 65 wt%-80 wt% fly ash. The mixture was formed into granules and steam-curing the at 97°C for 12 h, followed by heating at 800°C for 1 h. The results show that adding 1.0 wt% Na2O to the mixture of fly ash and CaO can efficiently promote the hydrothermal reaction. Belite cement with practicable strength and characterized by rapid setting and high sulfate attack resistance was synthesized.

Author(s):  
M. Melih Demirkan ◽  
Doina Morar ◽  
Ahmet H. Aydilek ◽  
Eric A. Seagren ◽  
Alice Tsai

Alloy Digest ◽  
2003 ◽  
Vol 52 (12) ◽  

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.


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

1987 ◽  
Vol 104 ◽  
Author(s):  
S. Hahn ◽  
M. Arst ◽  
K. N. Ritz ◽  
S. Shatas ◽  
H. J. Stein ◽  
...  

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.


Carbon ◽  
2013 ◽  
Vol 60 ◽  
pp. 307-316 ◽  
Author(s):  
Alum Jung ◽  
Suenghoon Han ◽  
Teawon Kim ◽  
Won Joon Cho ◽  
Kun-Hong Lee

Author(s):  
Isabelle Delvallée-Nunio ◽  
Olivier Loiseau ◽  
Daniel Monhardt ◽  
Audrey Buiron ◽  
Franck Dubois

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.


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