Effects of water chemistry transients on crack growth rate of nickel-based weld metals

Aki Toivonen, Pekka Moilanen, Pertti Aaltonen, Laura Taivalaho, Erkki Muttilainen

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientific

2 Citations (Scopus)

Abstract

Stress corrosion crack growth rates of Alloy 182 and 82 weld metals in thermally aged (400°C/200 h) conditions have been measured in simulated BWR conditions. The effects of water chemistry impurity concentration transients on crack growth rate and cracking morphology have been studied. The time for onset of accelerated crack growth due to impurity / conductivity transient was measured when the conductivity of the coolant was adjusted by additions of sulphate as H2SO4 in the range of 10-100 ppb. Crack growth was monitored using potential drop method during slow rising displacement testing applied to 10x10 mm2 cross section, fatigue pre-cracked, three point bend specimens. The delay in crack growth rate slow down after returning to high purity water was also measured. In the tests an increase in the crack growth rate became visible in Alloy 182 within 25-45 h after sulphate was introduced into the bulk water. Although there is no reason or consistent data to support a permanent increase in crack growth rate caused by a sulphate transient, the measured crack growth rate did not return back to the level prevailing prior to the transient. In Alloy 82 no crack growth was observed with any of the applied conditions of this study. Crack growth rates were measured also for cold deformed AISI 316NG and furnace sensitised AISI 304 stainless steels, as reference.
Original languageEnglish
Title of host publication Plant Life Management
Subtitle of host publicationProgress for structural integrity
Place of PublicationEspoo
PublisherVTT Technical Research Centre of Finland
Pages223-239
ISBN (Electronic)951-38-6281-X
ISBN (Print)951-38-6280-1
Publication statusPublished - 2003
MoE publication typeB3 Non-refereed article in conference proceedings
EventPlant Life Management: Progress for structural integrity - Espoo, Finland
Duration: 1 Jan 20021 Jan 2002

Publication series

NameVTT Symposium
PublisherVTT
Number227
ISSN (Print)0357-9387
ISSN (Electronic)1455-0873

Seminar

SeminarPlant Life Management
CountryFinland
CityEspoo
Period1/01/021/01/02

Fingerprint

Crack propagation
Welds
Nickel
Metals
Water
Impurities
Coolants
Furnaces
Stainless steel
Fatigue of materials
Corrosion
Testing
Sulfates

Cite this

Toivonen, A., Moilanen, P., Aaltonen, P., Taivalaho, L., & Muttilainen, E. (2003). Effects of water chemistry transients on crack growth rate of nickel-based weld metals. In Plant Life Management: Progress for structural integrity (pp. 223-239). Espoo: VTT Technical Research Centre of Finland. VTT Symposium, No. 227
Toivonen, Aki ; Moilanen, Pekka ; Aaltonen, Pertti ; Taivalaho, Laura ; Muttilainen, Erkki. / Effects of water chemistry transients on crack growth rate of nickel-based weld metals. Plant Life Management: Progress for structural integrity. Espoo : VTT Technical Research Centre of Finland, 2003. pp. 223-239 (VTT Symposium; No. 227).
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abstract = "Stress corrosion crack growth rates of Alloy 182 and 82 weld metals in thermally aged (400°C/200 h) conditions have been measured in simulated BWR conditions. The effects of water chemistry impurity concentration transients on crack growth rate and cracking morphology have been studied. The time for onset of accelerated crack growth due to impurity / conductivity transient was measured when the conductivity of the coolant was adjusted by additions of sulphate as H2SO4 in the range of 10-100 ppb. Crack growth was monitored using potential drop method during slow rising displacement testing applied to 10x10 mm2 cross section, fatigue pre-cracked, three point bend specimens. The delay in crack growth rate slow down after returning to high purity water was also measured. In the tests an increase in the crack growth rate became visible in Alloy 182 within 25-45 h after sulphate was introduced into the bulk water. Although there is no reason or consistent data to support a permanent increase in crack growth rate caused by a sulphate transient, the measured crack growth rate did not return back to the level prevailing prior to the transient. In Alloy 82 no crack growth was observed with any of the applied conditions of this study. Crack growth rates were measured also for cold deformed AISI 316NG and furnace sensitised AISI 304 stainless steels, as reference.",
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Toivonen, A, Moilanen, P, Aaltonen, P, Taivalaho, L & Muttilainen, E 2003, Effects of water chemistry transients on crack growth rate of nickel-based weld metals. in Plant Life Management: Progress for structural integrity. VTT Technical Research Centre of Finland, Espoo, VTT Symposium, no. 227, pp. 223-239, Plant Life Management, Espoo, Finland, 1/01/02.

Effects of water chemistry transients on crack growth rate of nickel-based weld metals. / Toivonen, Aki; Moilanen, Pekka; Aaltonen, Pertti; Taivalaho, Laura; Muttilainen, Erkki.

Plant Life Management: Progress for structural integrity. Espoo : VTT Technical Research Centre of Finland, 2003. p. 223-239 (VTT Symposium; No. 227).

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientific

TY - GEN

T1 - Effects of water chemistry transients on crack growth rate of nickel-based weld metals

AU - Toivonen, Aki

AU - Moilanen, Pekka

AU - Aaltonen, Pertti

AU - Taivalaho, Laura

AU - Muttilainen, Erkki

N1 - Project code: H2SU00363

PY - 2003

Y1 - 2003

N2 - Stress corrosion crack growth rates of Alloy 182 and 82 weld metals in thermally aged (400°C/200 h) conditions have been measured in simulated BWR conditions. The effects of water chemistry impurity concentration transients on crack growth rate and cracking morphology have been studied. The time for onset of accelerated crack growth due to impurity / conductivity transient was measured when the conductivity of the coolant was adjusted by additions of sulphate as H2SO4 in the range of 10-100 ppb. Crack growth was monitored using potential drop method during slow rising displacement testing applied to 10x10 mm2 cross section, fatigue pre-cracked, three point bend specimens. The delay in crack growth rate slow down after returning to high purity water was also measured. In the tests an increase in the crack growth rate became visible in Alloy 182 within 25-45 h after sulphate was introduced into the bulk water. Although there is no reason or consistent data to support a permanent increase in crack growth rate caused by a sulphate transient, the measured crack growth rate did not return back to the level prevailing prior to the transient. In Alloy 82 no crack growth was observed with any of the applied conditions of this study. Crack growth rates were measured also for cold deformed AISI 316NG and furnace sensitised AISI 304 stainless steels, as reference.

AB - Stress corrosion crack growth rates of Alloy 182 and 82 weld metals in thermally aged (400°C/200 h) conditions have been measured in simulated BWR conditions. The effects of water chemistry impurity concentration transients on crack growth rate and cracking morphology have been studied. The time for onset of accelerated crack growth due to impurity / conductivity transient was measured when the conductivity of the coolant was adjusted by additions of sulphate as H2SO4 in the range of 10-100 ppb. Crack growth was monitored using potential drop method during slow rising displacement testing applied to 10x10 mm2 cross section, fatigue pre-cracked, three point bend specimens. The delay in crack growth rate slow down after returning to high purity water was also measured. In the tests an increase in the crack growth rate became visible in Alloy 182 within 25-45 h after sulphate was introduced into the bulk water. Although there is no reason or consistent data to support a permanent increase in crack growth rate caused by a sulphate transient, the measured crack growth rate did not return back to the level prevailing prior to the transient. In Alloy 82 no crack growth was observed with any of the applied conditions of this study. Crack growth rates were measured also for cold deformed AISI 316NG and furnace sensitised AISI 304 stainless steels, as reference.

M3 - Conference article in proceedings

SN - 951-38-6280-1

T3 - VTT Symposium

SP - 223

EP - 239

BT - Plant Life Management

PB - VTT Technical Research Centre of Finland

CY - Espoo

ER -

Toivonen A, Moilanen P, Aaltonen P, Taivalaho L, Muttilainen E. Effects of water chemistry transients on crack growth rate of nickel-based weld metals. In Plant Life Management: Progress for structural integrity. Espoo: VTT Technical Research Centre of Finland. 2003. p. 223-239. (VTT Symposium; No. 227).