### Abstract

_{NDT}temperature indexing parameter and the ASME KIR-reference curve with respect to crack arrest toughness, has been evaluated. Based on an analysis of the original ASME K

_{Ia}data, it was established that inherently, the ASME K

_{IR}-reference curve corresponds to an overall 5% lower bound curve with respect to crack arrest. It was shown that the scatter of crack arrest toughness is essentially material independent and has a standard deviation (S.D.) of 18% and the temperature dependence of K

_{Ia}has the same form as predicted by the master curve for crack initiation toughness. The ‘built in’ offset between the mean 100 MPa√m crack arrest temperature, TK

_{Ia}, and RT

_{NDT}is 38°C (TK

_{Ia}=RT

_{NDT}+38°C) and the experimental relation between TK

_{Ia}and NDT is, TK

_{Ia}=NDT+28°C. The K

_{IR}-reference curve using NDT as reference temperature will be conservative with respect to the general 5% lower bound K

_{Ia}(5%)-curve, with a 75% confidence. The use of RT

_{NDT}, instead of NDT, will generally increase the degree of conservatism, both for non-irradiated as well as irradiated materials, close to a 95% confidence level. This trend is pronounced for materials with Charpy-V upper shelf energies below 100 J. It is shown that the K

_{IR}-curve effectively constitutes a deterministic lower bound curve for crack arrest The findings are valid both for nuclear pressure vessel plates, forgings and welds.

Original language | English |
---|---|

Pages (from-to) | 185-199 |

Number of pages | 15 |

Journal | Nuclear Engineering and Design |

Volume | 206 |

Issue number | 2-3 |

DOIs | |

Publication status | Published - 2001 |

MoE publication type | A1 Journal article-refereed |

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_{IR}-reference curve with respect to crack arrest.

*Nuclear Engineering and Design*,

*206*(2-3), 185-199. https://doi.org/10.1016/S0029-5493(00)00434-9

}

_{IR}-reference curve with respect to crack arrest',

*Nuclear Engineering and Design*, vol. 206, no. 2-3, pp. 185-199. https://doi.org/10.1016/S0029-5493(00)00434-9

**Conservatism of ASME K _{IR}-reference curve with respect to crack arrest.** / Wallin, Kim (Corresponding Author); Rintamaa, Rauno; Nagel, G.

Research output: Contribution to journal › Article › Scientific › peer-review

TY - JOUR

T1 - Conservatism of ASME KIR-reference curve with respect to crack arrest

AU - Wallin, Kim

AU - Rintamaa, Rauno

AU - Nagel, G.

PY - 2001

Y1 - 2001

N2 - The conservatism of the RTNDT temperature indexing parameter and the ASME KIR-reference curve with respect to crack arrest toughness, has been evaluated. Based on an analysis of the original ASME KIa data, it was established that inherently, the ASME KIR-reference curve corresponds to an overall 5% lower bound curve with respect to crack arrest. It was shown that the scatter of crack arrest toughness is essentially material independent and has a standard deviation (S.D.) of 18% and the temperature dependence of KIa has the same form as predicted by the master curve for crack initiation toughness. The ‘built in’ offset between the mean 100 MPa√m crack arrest temperature, TKIa, and RTNDT is 38°C (TKIa=RTNDT+38°C) and the experimental relation between TKIa and NDT is, TKIa=NDT+28°C. The KIR-reference curve using NDT as reference temperature will be conservative with respect to the general 5% lower bound KIa(5%)-curve, with a 75% confidence. The use of RTNDT, instead of NDT, will generally increase the degree of conservatism, both for non-irradiated as well as irradiated materials, close to a 95% confidence level. This trend is pronounced for materials with Charpy-V upper shelf energies below 100 J. It is shown that the KIR-curve effectively constitutes a deterministic lower bound curve for crack arrest The findings are valid both for nuclear pressure vessel plates, forgings and welds.

AB - The conservatism of the RTNDT temperature indexing parameter and the ASME KIR-reference curve with respect to crack arrest toughness, has been evaluated. Based on an analysis of the original ASME KIa data, it was established that inherently, the ASME KIR-reference curve corresponds to an overall 5% lower bound curve with respect to crack arrest. It was shown that the scatter of crack arrest toughness is essentially material independent and has a standard deviation (S.D.) of 18% and the temperature dependence of KIa has the same form as predicted by the master curve for crack initiation toughness. The ‘built in’ offset between the mean 100 MPa√m crack arrest temperature, TKIa, and RTNDT is 38°C (TKIa=RTNDT+38°C) and the experimental relation between TKIa and NDT is, TKIa=NDT+28°C. The KIR-reference curve using NDT as reference temperature will be conservative with respect to the general 5% lower bound KIa(5%)-curve, with a 75% confidence. The use of RTNDT, instead of NDT, will generally increase the degree of conservatism, both for non-irradiated as well as irradiated materials, close to a 95% confidence level. This trend is pronounced for materials with Charpy-V upper shelf energies below 100 J. It is shown that the KIR-curve effectively constitutes a deterministic lower bound curve for crack arrest The findings are valid both for nuclear pressure vessel plates, forgings and welds.

U2 - 10.1016/S0029-5493(00)00434-9

DO - 10.1016/S0029-5493(00)00434-9

M3 - Article

VL - 206

SP - 185

EP - 199

JO - Nuclear Engineering and Design

JF - Nuclear Engineering and Design

SN - 0029-5493

IS - 2-3

ER -

_{IR}-reference curve with respect to crack arrest. Nuclear Engineering and Design. 2001;206(2-3):185-199. https://doi.org/10.1016/S0029-5493(00)00434-9