Dependence of re-embrittlement rate after annealing on the copper, nickel and phosphorus contents in model alloys

Matti Valo, Ulla Ehrnstén, Jyrki Kohopää, Luigi Debarberis, Alexander Krykukov, Rauno Rintamaa

Research output: Contribution to journalArticleScientificpeer-review

Abstract

Irradiation embrittlement rate as well as the re-embrittlement rate after annealing of pressure vessel steels can in general be described by the copper, phosphorus and nickel contents of the materials. In the current study embrittlement and re-embrittlement rate of 32 different model alloys were measured using sub-size CH-V specimens of dimensions 3 × 4 × 27 mm. The impurity and alloy elements of the model alloys were varied within the limits Cu: 0−1.0 wt-%, P = 0−0.040 wt-% and Ni: 0−2.0 wt-% relatively evenly. The specimens were originally irradiated in the high flux reactor in Petten into a neutron fluence of 0.3×1019n/cm2, E >1 MeV and re-irradiated after the annealing treatment in the Loviisa power reactor into a fluence of 1.0 × 1019n/cm2, E > 1 MeV. In the paper the irradiation and re-irradiation embrittlement rate has been modeled based on the Cu, P and Ni contents of the alloys. Re-irradiation rate was found to be clearly lower than the original irradiation rate except for small corner in the element space, i.e., no nickel, low copper and high phosphorus alloys. Phosphorus coefficient in the re-irradiation shift function is relatively two times higher than in the original irradiation shift function. Many of the alloys in the IAI-condition show intergranular type fracture (IGF). However, the effect of the change of the fracture mode from cleavage to IGF on transition temperature shift remains open. The dependence of irradiation embrittlement, annealing and re-embrittlement behavior on the copper, phosphorus and nickel contents is still not solved, one reason being the relatively limited variation of the key elements in the materials. Model alloys offer a good variation matrix of the elements even, if the measured data cannot be directly applied to real steels.
Original languageEnglish
Pages (from-to)164 - 178
Number of pages15
JournalJournal of ASTM International
Volume1
Issue number4
DOIs
Publication statusPublished - 2004
MoE publication typeA1 Journal article-refereed

Fingerprint

Embrittlement
Nickel
Phosphorus
Copper
Irradiation
Annealing
Steel
Transition Temperature
Neutrons
Steel structures
Superconducting transition temperature
Pressure
Impurities
Fluxes
Re-Irradiation

Keywords

  • alloy
  • annealing
  • cleavage fracture
  • intergranular fracture
  • irradiation embrittlement
  • re-embrittlement
  • subsize CH-V test

Cite this

Valo, Matti ; Ehrnstén, Ulla ; Kohopää, Jyrki ; Debarberis, Luigi ; Krykukov, Alexander ; Rintamaa, Rauno. / Dependence of re-embrittlement rate after annealing on the copper, nickel and phosphorus contents in model alloys. In: Journal of ASTM International. 2004 ; Vol. 1, No. 4. pp. 164 - 178.
@article{f990e602d88741ec94a2d23cb8b1a11d,
title = "Dependence of re-embrittlement rate after annealing on the copper, nickel and phosphorus contents in model alloys",
abstract = "Irradiation embrittlement rate as well as the re-embrittlement rate after annealing of pressure vessel steels can in general be described by the copper, phosphorus and nickel contents of the materials. In the current study embrittlement and re-embrittlement rate of 32 different model alloys were measured using sub-size CH-V specimens of dimensions 3 × 4 × 27 mm. The impurity and alloy elements of the model alloys were varied within the limits Cu: 0−1.0 wt-{\%}, P = 0−0.040 wt-{\%} and Ni: 0−2.0 wt-{\%} relatively evenly. The specimens were originally irradiated in the high flux reactor in Petten into a neutron fluence of 0.3×1019n/cm2, E >1 MeV and re-irradiated after the annealing treatment in the Loviisa power reactor into a fluence of 1.0 × 1019n/cm2, E > 1 MeV. In the paper the irradiation and re-irradiation embrittlement rate has been modeled based on the Cu, P and Ni contents of the alloys. Re-irradiation rate was found to be clearly lower than the original irradiation rate except for small corner in the element space, i.e., no nickel, low copper and high phosphorus alloys. Phosphorus coefficient in the re-irradiation shift function is relatively two times higher than in the original irradiation shift function. Many of the alloys in the IAI-condition show intergranular type fracture (IGF). However, the effect of the change of the fracture mode from cleavage to IGF on transition temperature shift remains open. The dependence of irradiation embrittlement, annealing and re-embrittlement behavior on the copper, phosphorus and nickel contents is still not solved, one reason being the relatively limited variation of the key elements in the materials. Model alloys offer a good variation matrix of the elements even, if the measured data cannot be directly applied to real steels.",
keywords = "alloy, annealing, cleavage fracture, intergranular fracture, irradiation embrittlement, re-embrittlement, subsize CH-V test",
author = "Matti Valo and Ulla Ehrnst{\'e}n and Jyrki Kohop{\"a}{\"a} and Luigi Debarberis and Alexander Krykukov and Rauno Rintamaa",
note = "Project code: G4SU00284",
year = "2004",
doi = "10.1520/JAI11351",
language = "English",
volume = "1",
pages = "164 -- 178",
journal = "Journal of ASTM International",
issn = "1546-962X",
publisher = "American Society for Testing and Materials ASTM",
number = "4",

}

Dependence of re-embrittlement rate after annealing on the copper, nickel and phosphorus contents in model alloys. / Valo, Matti; Ehrnstén, Ulla; Kohopää, Jyrki; Debarberis, Luigi; Krykukov, Alexander; Rintamaa, Rauno.

In: Journal of ASTM International, Vol. 1, No. 4, 2004, p. 164 - 178.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Dependence of re-embrittlement rate after annealing on the copper, nickel and phosphorus contents in model alloys

AU - Valo, Matti

AU - Ehrnstén, Ulla

AU - Kohopää, Jyrki

AU - Debarberis, Luigi

AU - Krykukov, Alexander

AU - Rintamaa, Rauno

N1 - Project code: G4SU00284

PY - 2004

Y1 - 2004

N2 - Irradiation embrittlement rate as well as the re-embrittlement rate after annealing of pressure vessel steels can in general be described by the copper, phosphorus and nickel contents of the materials. In the current study embrittlement and re-embrittlement rate of 32 different model alloys were measured using sub-size CH-V specimens of dimensions 3 × 4 × 27 mm. The impurity and alloy elements of the model alloys were varied within the limits Cu: 0−1.0 wt-%, P = 0−0.040 wt-% and Ni: 0−2.0 wt-% relatively evenly. The specimens were originally irradiated in the high flux reactor in Petten into a neutron fluence of 0.3×1019n/cm2, E >1 MeV and re-irradiated after the annealing treatment in the Loviisa power reactor into a fluence of 1.0 × 1019n/cm2, E > 1 MeV. In the paper the irradiation and re-irradiation embrittlement rate has been modeled based on the Cu, P and Ni contents of the alloys. Re-irradiation rate was found to be clearly lower than the original irradiation rate except for small corner in the element space, i.e., no nickel, low copper and high phosphorus alloys. Phosphorus coefficient in the re-irradiation shift function is relatively two times higher than in the original irradiation shift function. Many of the alloys in the IAI-condition show intergranular type fracture (IGF). However, the effect of the change of the fracture mode from cleavage to IGF on transition temperature shift remains open. The dependence of irradiation embrittlement, annealing and re-embrittlement behavior on the copper, phosphorus and nickel contents is still not solved, one reason being the relatively limited variation of the key elements in the materials. Model alloys offer a good variation matrix of the elements even, if the measured data cannot be directly applied to real steels.

AB - Irradiation embrittlement rate as well as the re-embrittlement rate after annealing of pressure vessel steels can in general be described by the copper, phosphorus and nickel contents of the materials. In the current study embrittlement and re-embrittlement rate of 32 different model alloys were measured using sub-size CH-V specimens of dimensions 3 × 4 × 27 mm. The impurity and alloy elements of the model alloys were varied within the limits Cu: 0−1.0 wt-%, P = 0−0.040 wt-% and Ni: 0−2.0 wt-% relatively evenly. The specimens were originally irradiated in the high flux reactor in Petten into a neutron fluence of 0.3×1019n/cm2, E >1 MeV and re-irradiated after the annealing treatment in the Loviisa power reactor into a fluence of 1.0 × 1019n/cm2, E > 1 MeV. In the paper the irradiation and re-irradiation embrittlement rate has been modeled based on the Cu, P and Ni contents of the alloys. Re-irradiation rate was found to be clearly lower than the original irradiation rate except for small corner in the element space, i.e., no nickel, low copper and high phosphorus alloys. Phosphorus coefficient in the re-irradiation shift function is relatively two times higher than in the original irradiation shift function. Many of the alloys in the IAI-condition show intergranular type fracture (IGF). However, the effect of the change of the fracture mode from cleavage to IGF on transition temperature shift remains open. The dependence of irradiation embrittlement, annealing and re-embrittlement behavior on the copper, phosphorus and nickel contents is still not solved, one reason being the relatively limited variation of the key elements in the materials. Model alloys offer a good variation matrix of the elements even, if the measured data cannot be directly applied to real steels.

KW - alloy

KW - annealing

KW - cleavage fracture

KW - intergranular fracture

KW - irradiation embrittlement

KW - re-embrittlement

KW - subsize CH-V test

U2 - 10.1520/JAI11351

DO - 10.1520/JAI11351

M3 - Article

VL - 1

SP - 164

EP - 178

JO - Journal of ASTM International

JF - Journal of ASTM International

SN - 1546-962X

IS - 4

ER -