Current understanding of radiation-induced degradation in light water reactor structural materials

Figures & data

Figure 1 Examples of (a) intensity distribution of neutrons and gamma rays and (b) neutron energy spectrum within the RPV in a PWR (figures drawn using radiation transport calculation data from [8])

Figure 2 Maximum fluence or dose and typical temperature for 40-year operation of a reactor pressure vessel and core internals

Figure 3 Schematic embrittlement trends in (a) low-flux BWR and (b) high-flux PWR conditions

Figure 4 Comparison of transition temperature shifts between surveillance data and MTR data: (a) high-Cu BWR surveillance material and (b) low-Cu PWR surveillance material. The data from references [32,33] are replotted and trends are shown

Figure 5 Examples of 3DAP atom maps showing (a) Cu-rich clusters and (b) Mn–Ni–Si clusters in A533B steels irradiated with heavy ions to 1 dpa at 290ºC (courtesy of Katsuhiko Fujii of the Institute of Nuclear Safety System, Inc.). It should be noted that Mn–Ni–Si clusters are also found in (a)

Figure 6 CDB spectra in 0.12%Cu A533B steels irradiated in a MTR at 290°C [37]

Figure 7 3DAP data of density and diameter for solute clusters in MTR-irradiated A533B steels with various Cu and Ni contents [77]. Reprinted, with permission, from the Journal of ASTM International, Volume 6, Issue 7, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428

Figure 8 Relationship between cluster volume fraction (V _f ^1/2) and transition temperature shift (ΔRT _NDT) in surveillance specimens [59]. Reprinted, with permission, from the Journal of ASTM International, Volume 7, Issue 3, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428

Figure 9 Effect of dose rate on the number of vacancy jumps from kinetic Monte Carlo calculations [94]

Figure 10 TEM images showing interstitial dislocation loops in A533B steels irradiated with heavy ions to 1 dpa at 290°C: weak-beam images with diffraction vectors (a) g = 011 and (b) g = 200 close to the [011] pole [98]

Figure 11 Positron lifetime data in weld surveillance specimens (0.13%Cu for Doel-1 and 0.30%Cu for Doel-2) [53]

Figure 12 Irradiation hardening (Δσ_y ) versus transition temperature shift (ΔT _41J) in MTR-irradiated A533B steels with various levels of P segregation at GBs (ΔC_P ^gb) [121]. Reprinted, with permission, from the Journal of ASTM International, Volume 6, Issue 7, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428

Figure 13 Plots of master curve reference temperature shift ΔT ₀ versus Charpy transition temperature shift ΔT _41J for A533B steel data sets containing high-shift data. The dotted line shows the correlation given by Sokolov and Nanstad [148]

Figure 14 Constant load SCC test data in the stress ratio to yield strength (σ/σ_y ) versus dose maps in (a) BWR water conditions (288°C, 32 ppm DO) and PWR water conditions (320–340°C, 2.7 ppm DH)

Figure 15 Dose dependence of CGR in BWR water conditions at both high ECP (>150 mV_SHE) and low ECP (<–200 mV_SHE)

Figure 16 CGR data of 304 SSs from in-pile tests and PIEs in BWR NWC water conditions [208]

Figure 17 TEM images showing microstructural features observed in CW type 316 SSs PWR-irradiated to 53 dpa: (a) rel-rod dark field image of dislocation loops; (b) dark field image of dislocation loops and black dots; (c) dark field image of Ni₃Si precipitates; and (d) defocused image of bubbles [220]

Figure 18 Change in (a) yield strength and (b) fracture elongation in LWR-irradiated SSs

Figure 19 Near-surface deformation microstructure in CW type 316 SSs deformed to 3% at 320°C: (a) irradiated to 35 dpa showing coarse slips and surface steps with an enlarged image of the dislocation channel and (b) unirradiated showing tangled dislocations [245]

Figure 20 Schematic illustration depicting (a) three types of interactions of dislocation channels with GBs; (b) SEM image showing dislocation pileups in irradiated CW type 316 SSs after slow deformation to 13% at 320°C; and (c) TEM image showing channel transfer in irradiated CW type 316 SSs after slow deformation to ∼3% at 320°C

Figure 21 Typical solute distributions across a GB and changes in GB segregation of Cr, Ni and Si with dose in LWR-irradiated SSs

Figure 22 Data of stress relaxation in type 304 and 316L SSs under MTR irradiation at 288°C

Figure 23 Dose-dependent changes in IASCC, mechanical properties and RIS in PWR-irradiated CW type 316 SSs [298]

Figure 24 TEM image and solute distribution near the IASCC crack tip in CW type 316 SSs PWR-irradiated to 38 dpa after the constant load test at 750 MPa in PWR water conditions [304]

Figure 25 Schematic illustration depicting various processes related to IASCC

Figure 26 IG cracks formed in PWR-irradiated CW type 316 SSs after slow deformation to ∼3% at 300°C in an argon atmosphere [245]

Figure 27 Contribution of localized deformation as measured by the weighted average channel height to cracking in SSs irradiated with protons to 1–5 dpa and SCC-tested in BWR water conditions [247]

Figure 28 Distribution of Fe, Ni, Cr and O in the cross section of the surface oxide layer in type 316 SSs PWR-irradiated to 20 dpa after immersion in PWR water conditions for 1000 h [322]

Figure 29 Swelling data in various SSs irradiated at LWR-relevant temperatures of 290–390ºC

Figure 30 Fracture toughness data in LWR-irradiated SSs tested at ∼300ºC

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