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Carbide Composition Changes in Power Plant Steels as a Method of Remanent Creep Life Prediction

By Rachel Clare Thomson
Publisher: Department of Materials Science and Metallurgy
Year: 1992
OAI identifier: oai:www.repository.cam.ac.uk:1810/221882
Provided by: Apollo

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Citations

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  4. (1970). 2.2.1 Morphology and carbide precipitation Bainite consists of non-lamellar aggregates of ferrite and carbides, the ferrite being in the form of thin plates approximately 10 j,tm long and 0.2 j,tm thick, commonly referred to as sheaves (Hehemann,
  5. (1978). 3.3 Equilibrium compositions of cementite and ferrite For many years the equilibrium compositions of the various carbides in alloyed steels were not known. Vengopalan and Kirkaldy
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  53. Ex-service' 12Cr1MoV steel 700°C Fe Cr Mo Mn C Fe Cr Mo Mn C
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  57. (1987). Figure 2.9: The formation of martensite (Bhadeshia, doi
  58. (1950). Figure 5.34: A self'ctf'd area electron diffraction pattern from thf' rnartensitic region f'xhihiting thf' well known Bagaryatski
  59. Figure 5.37: Carhon ('xtractioll r('plica from sl><,clrncnt('mpN('d for 1048 hours at 565°C showing that t1l<'microstructur(' consists pr('dolllinantly of largc M7C3 and fill(, M2C particles.
  60. (1986). Figure 5.69: Illustration of the dependence of the enrichment of cementite on the particle size calculated at 565°C using the finite difference model. 145CHAPTER 6 !Cr!Mo!
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  65. (1969). In this work intrinsic chemical diffusion coefficients are used from the work of Fridberg et al.
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  75. (1952). Lower bainite a. High dislocation density
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  106. t .I:l 0.008 :I 600 bi .•. c:l • .. ~ 0.006 8- •• a 400 .~ .,
  107. (2000). t) ••• 600 ::l - ftl ••• t) Cl. 8 400 t) E200 o o 1000 2000 3000 4000 Time /s 5000 0.014 ~ 0.012 c:l Cl:! ~ 0.01 ..c:l .•.. till 0.008 c:l t) -t) 0.006 ~ ...• .•..
  108. (1961). Table 1.3: The effect of temperature on rupture life.
  109. Table 6.1: Chemical composition of the ~Cr~Mot V steel in wt.%
  110. (1970). Table 8.2: Measurements of the diffusion of chromium in ferrite and cementite at 486°C. DO'/m2s-1 D8/m2s-1 Bowen and Leak
  111. Tempering Correlation Average Cr Average particle time fHours coefficient cone. fwt.% size fum
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  117. (1969). The calculated value of the diffusion coefficients at the three temperatures were then used to calculate the activation energy for the diffusion of Cr in ferrite using the Arhenius relationship
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  121. (1984). The effect of temperature on rupture life is illustrated in Table 1.3. This is based on the 15650
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  131. (1979). The material described in this chapter has been accepted for publication in Surface Science.
  132. (1992). The material described in this chapter has been published in Materials Science and Engineering A,
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  134. (1990). The newest indicator of thermal history developed by
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  145. (1956). The tempering of plain carbon steels',
  146. The Widmanstatten ferrite type M2C carbides were found to have the orientation relationship (Ol1)a 11 (0001 )Mo2C (100)a 11 (2IIO)Mo2c [lOO]a 11 [2110]Mo2c, which is also that describing the precipitation of M2C in tempered martensite.
  147. (1989). Theoretical Analysis of Changes in Cementite Composition During Tempering of Bainite', doi
  148. (1961). Theorie der Alterung von NiederschHigendurch Umlosen',
  149. (1987). Theory for allotriomorphic ferrite formation in steel weld deposits', Welding metallurgy of structural steels,
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  151. (1966). Thermal Expansion of Cementite and Other Phases',
  152. (1965). Thermodynamics of dilute interstitial solid solutions with dual site occupancy and its applications to the diffusion of carbon in a-iron',
  153. (1966). These compositions are in general agreement with those of Beech and
  154. (1975). Thickening Kinetics of proeutectoid ferrite plates in Fe-C alloys', doi
  155. (1978). This is a Cr-rich carbide with the trigonal structure of Cr7C3, having a solubility of Fe up to 60% (although Titchmarsh
  156. Time /Hours Cr /wt.%
  157. (1971). Time at 700°C Lattice parameter
  158. (1956). Transformation kinetics during continuous cooling', doi
  159. (1987). Worked Examples in the Geometry of Crystals', The Institute of Metals,
  160. (1982). X-ray powder diffraction evidence for the incorporation of Wand Mo into M23C6 extracted from high temperature alloys', doi

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