Ductile-brittle transition of polycrystalline iron and iron-chromium alloys

Masaki Tanaka, Angus J. Wilkinson, Steve G. Roberts

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Fracture toughness of polycrystalline Fe, Fe-3%Cr and Fe-9%Cr was measured by four-point bending of pre-cracked specimens at temperatures between 77 K and 150 K and strain rates between 4.46 × 10-4 and 2.23 × 10-2 s-1. For all materials, fracture behaviour changed with increasing temperature from brittle to ductile at a distinct brittle-ductile transition temperature (Tc), which increased with increasing strain rate. At low strain rates, an Arrhenius relation was found between Tc and strain rate in each material. At high strain rates, Tc was at slightly higher values than those expected from extrapolation of the Arrhenius relation from lower strain rates. This shift of Tc was associated with twinning near the crack tip. For each material, use of an Arrhenius relation for tests at strain rates at which specimens showed twinning gave the same activation energy as for the low strain rate tests. The values of activation energy for the brittle-ductile transition of polycrystalline Fe, Fe-3%Cr and Fe-9%Cr were found to be 0.21, 0.15 and 0.10 eV, respectively, indicating that the activation energy for dislocation glide decreases with increasing chromium concentration in iron.

Original languageEnglish
Pages (from-to)305-311
Number of pages7
JournalJournal of Nuclear Materials
Volume378
Issue number3
DOIs
Publication statusPublished - Sep 1 2008
Externally publishedYes

Fingerprint

Chromium Alloys
ductile-brittle transition
chromium alloys
Chromium alloys
iron alloys
Iron alloys
strain rate
Strain rate
Iron
iron
Activation energy
Twinning
twinning
activation energy
crack tips
Chromium
fracture strength
Extrapolation
Crack tips
Superconducting transition temperature

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Materials Science(all)
  • Nuclear Energy and Engineering

Cite this

Ductile-brittle transition of polycrystalline iron and iron-chromium alloys. / Tanaka, Masaki; Wilkinson, Angus J.; Roberts, Steve G.

In: Journal of Nuclear Materials, Vol. 378, No. 3, 01.09.2008, p. 305-311.

Research output: Contribution to journalArticle

Tanaka, Masaki ; Wilkinson, Angus J. ; Roberts, Steve G. / Ductile-brittle transition of polycrystalline iron and iron-chromium alloys. In: Journal of Nuclear Materials. 2008 ; Vol. 378, No. 3. pp. 305-311.
@article{2028435168f8403c90387d2a08ffa9f6,
title = "Ductile-brittle transition of polycrystalline iron and iron-chromium alloys",
abstract = "Fracture toughness of polycrystalline Fe, Fe-3{\%}Cr and Fe-9{\%}Cr was measured by four-point bending of pre-cracked specimens at temperatures between 77 K and 150 K and strain rates between 4.46 × 10-4 and 2.23 × 10-2 s-1. For all materials, fracture behaviour changed with increasing temperature from brittle to ductile at a distinct brittle-ductile transition temperature (Tc), which increased with increasing strain rate. At low strain rates, an Arrhenius relation was found between Tc and strain rate in each material. At high strain rates, Tc was at slightly higher values than those expected from extrapolation of the Arrhenius relation from lower strain rates. This shift of Tc was associated with twinning near the crack tip. For each material, use of an Arrhenius relation for tests at strain rates at which specimens showed twinning gave the same activation energy as for the low strain rate tests. The values of activation energy for the brittle-ductile transition of polycrystalline Fe, Fe-3{\%}Cr and Fe-9{\%}Cr were found to be 0.21, 0.15 and 0.10 eV, respectively, indicating that the activation energy for dislocation glide decreases with increasing chromium concentration in iron.",
author = "Masaki Tanaka and Wilkinson, {Angus J.} and Roberts, {Steve G.}",
year = "2008",
month = "9",
day = "1",
doi = "10.1016/j.jnucmat.2008.06.039",
language = "English",
volume = "378",
pages = "305--311",
journal = "Journal of Nuclear Materials",
issn = "0022-3115",
publisher = "Elsevier",
number = "3",

}

TY - JOUR

T1 - Ductile-brittle transition of polycrystalline iron and iron-chromium alloys

AU - Tanaka, Masaki

AU - Wilkinson, Angus J.

AU - Roberts, Steve G.

PY - 2008/9/1

Y1 - 2008/9/1

N2 - Fracture toughness of polycrystalline Fe, Fe-3%Cr and Fe-9%Cr was measured by four-point bending of pre-cracked specimens at temperatures between 77 K and 150 K and strain rates between 4.46 × 10-4 and 2.23 × 10-2 s-1. For all materials, fracture behaviour changed with increasing temperature from brittle to ductile at a distinct brittle-ductile transition temperature (Tc), which increased with increasing strain rate. At low strain rates, an Arrhenius relation was found between Tc and strain rate in each material. At high strain rates, Tc was at slightly higher values than those expected from extrapolation of the Arrhenius relation from lower strain rates. This shift of Tc was associated with twinning near the crack tip. For each material, use of an Arrhenius relation for tests at strain rates at which specimens showed twinning gave the same activation energy as for the low strain rate tests. The values of activation energy for the brittle-ductile transition of polycrystalline Fe, Fe-3%Cr and Fe-9%Cr were found to be 0.21, 0.15 and 0.10 eV, respectively, indicating that the activation energy for dislocation glide decreases with increasing chromium concentration in iron.

AB - Fracture toughness of polycrystalline Fe, Fe-3%Cr and Fe-9%Cr was measured by four-point bending of pre-cracked specimens at temperatures between 77 K and 150 K and strain rates between 4.46 × 10-4 and 2.23 × 10-2 s-1. For all materials, fracture behaviour changed with increasing temperature from brittle to ductile at a distinct brittle-ductile transition temperature (Tc), which increased with increasing strain rate. At low strain rates, an Arrhenius relation was found between Tc and strain rate in each material. At high strain rates, Tc was at slightly higher values than those expected from extrapolation of the Arrhenius relation from lower strain rates. This shift of Tc was associated with twinning near the crack tip. For each material, use of an Arrhenius relation for tests at strain rates at which specimens showed twinning gave the same activation energy as for the low strain rate tests. The values of activation energy for the brittle-ductile transition of polycrystalline Fe, Fe-3%Cr and Fe-9%Cr were found to be 0.21, 0.15 and 0.10 eV, respectively, indicating that the activation energy for dislocation glide decreases with increasing chromium concentration in iron.

UR - http://www.scopus.com/inward/record.url?scp=49949111279&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=49949111279&partnerID=8YFLogxK

U2 - 10.1016/j.jnucmat.2008.06.039

DO - 10.1016/j.jnucmat.2008.06.039

M3 - Article

AN - SCOPUS:49949111279

VL - 378

SP - 305

EP - 311

JO - Journal of Nuclear Materials

JF - Journal of Nuclear Materials

SN - 0022-3115

IS - 3

ER -