Study on Hold-Time Effects in Environmental Fatigue Lifetime of Low-Alloy Steel and Austenitic Stainless Steel in Air and Under Simulated PWR Primary Water Conditions

Herbst, Matthias; Roth, Armin; Rudolph, Jürgen

doi:10.1007/978-3-319-67244-1_62

Cited by 2 publications

(4 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Accordingly, in this project has been invested to improve understanding of EAF in LWR conditions, e.g. [1,2,3]. The INCEFA-PLUS project was started to study the influences of the parameters strain range ∆ε, mean strain ε, surface roughness Rt, hold time th and environment on the fatigue life Nf of stainless steels of relevance for European LWRs.…”

Section: Incefa-plus (Increasing Safety In Npps Bymentioning

confidence: 99%

INCEFA-PLUS Project: Review of the test programme and main results

Dundulis

Grybėnas

Bruchhausen

et al. 2020

METAL 2020 Conference Proeedings

View full text Add to dashboard Cite

INCEFA-PLUS (INcreasing Safety in NPPs byCovering gaps in Environmental Fatigue Assessment) project characterized environmentally assisted fatigue of stainless steels in light water reactor environments. During this project more than 200 fatigue tests have been carried out in different laboratories across Europe in air and water environment. Most tests were performed on a single batch of 304L, an austenitic stainless steel alloys employed in NPPs. The tests addressed the effects of strain amplitude, hold time periods, material roughness and mean strain/stress on fatigue endurance. A limited number of tests was carried out on other batches of 304L and on X6 CrNiTi 18 10, a Ti stabilised steel used in VVERs. Additionally, activities on the effects of mean stress under strain control, testing at reduced environmental fatigue correction factor Fen, and different applications of hold time as well as biaxial fatigue tests have been carried out. The data obtained has been collected and standardised in an online environmental fatigue database MatDB.

show abstract

Section: Incefa-plus (Increasing Safety In Npps Bymentioning

confidence: 99%

INCEFA-PLUS Project: Review of the test programme and main results

Dundulis

Grybėnas

Bruchhausen

et al. 2020

METAL 2020 Conference Proeedings

View full text Add to dashboard Cite

show abstract

“…However, the low cycle fatigue lives predicted by CR-6909 do not reflect current pressurized water reactor (PWR) plant experience where no failures attributed to environmental fatigue have been observed so far where the loading conditions were known [2]. Furthermore, studies on laboratory specimens found experimental fatigue lives to be longer than predictions based on CR-6909 [5,6]. This indicates that the guidance provided by CR-6909 includes significant conservatism, which could potentially be reduced without loss of operational plant safety.…”

Section: Introductionmentioning

confidence: 98%

“…This indicates that the guidance provided by CR-6909 includes significant conservatism, which could potentially be reduced without loss of operational plant safety. Accordingly, EAF has received much attention in the last few years [5][6][7][8][9][10][11][12][13][14][15].…”

Section: Introductionmentioning

confidence: 99%

“…Similarly, a number of studies investigated the influence of the waveform and especially mean strain [8] and hold time periods on environmental fatigue [6,13]. While mean strain did not have a major effect on fatigue life, it turned out that at least under certain conditions, introducing hold times at some cycles during the fatigue life can extend the fatigue life of austenitic steels in the PWR environment.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of Austenitic Stainless Steels with Regard to Environmentally Assisted Fatigue in Simulated Light Water Reactor Conditions

Bruchhausen

Dundulis

McLennan

et al. 2021

Metals

View full text Add to dashboard Cite

A substantial amount of research effort has been applied to the field of environmentally assisted fatigue (EAF) due to the requirement to account for the EAF behaviour of metals for existing and new build nuclear power plants. We present the results of the European project INcreasing Safety in NPPs by Covering Gaps in Environmental Fatigue Assessment (INCEFA-PLUS), during which the sensitivities of strain range, environment, surface roughness, mean strain and hold times, as well as their interactions on the fatigue life of austenitic steels has been characterized. The project included a test campaign, during which more than 250 fatigue tests were performed. The tests did not reveal a significant effect of mean strain or hold time on fatigue life. An empirical model describing the fatigue life as a function of strain rate, environment and surface roughness is developed. There is evidence for statistically significant interaction effects between surface roughness and the environment, as well as between surface roughness and strain range. However, their impact on fatigue life is so small that they are not practically relevant and can in most cases be neglected. Reducing the environmental impact on fatigue life by modifying the temperature or strain rate leads to an increase of the fatigue life in agreement with predictions based on NUREG/CR-6909. A limited sub-programme on the sensitivity of hold times at elevated temperature at zero force conditions and at elevated temperature did not show the beneficial effect on fatigue life found in another study.

show abstract

Study on Hold-Time Effects in Environmental Fatigue Lifetime of Low-Alloy Steel and Austenitic Stainless Steel in Air and Under Simulated PWR Primary Water Conditions

Cited by 2 publications

References 13 publications

INCEFA-PLUS Project: Review of the test programme and main results

INCEFA-PLUS Project: Review of the test programme and main results

Characterization of Austenitic Stainless Steels with Regard to Environmentally Assisted Fatigue in Simulated Light Water Reactor Conditions

Contact Info

Product

Resources

About