Dynamic strain aging in the high-temperature low-cycle fatigue of SA508 Cl. 3 forging steel

The effect of dynamic strain aging on cyclic stress response and fatigue resistance of ASME SA508 C1.3 forging steel for nuclear reactor pressure vessels has been evaluated in the temperature range of room temperature to 500 degrees C. Total strain ranges and strain rates were varied from 0.7 to 2.0% and from 4X10(-4) to 1X10(-2) s(-1) respectively. The cyclic stress response depended on the testing temperature, strain rate, and strain range. Generally, the initial cyclic hardening was immediately followed by cyclic softening at all strain rates. However, at 300 degrees C, the operating temperature of nuclear reactor pressure vessels, the variation of cyclic stress amplitude showed the primary and secondary hardening stages dependent on the strain rate and strain range. Dynamic strain aging was manifested by enhanced cyclic hardening, distinguished secondary hardening, and negative strain rate sensitivity. A modified cell shuttling model was described for the onset of the secondary hardening due to the dynamic strain aging and it was in good agreement with the experimental results. Fatigue life increased with increase in strain rate at all testing temperatures. Specifically the fatigue life was longer at the dynamic strain aging temperature. Further, the dynamic strain aging was easy to initiate the crack, while crack propagation was retarded by crack branching and suppression of plastic zone, hence the dynamic strain aging caused the improvement of fatigue resistance.
Publisher
Elsevier Science Bv
Issue Date
1995
Language
ENG
Keywords

PRESSURE-VESSEL STEELS; DEFORMATION

Citation

JOURNAL OF NUCLEAR MATERIALS, v.226, no.1-2, pp.216 - 225

ISSN
0022-3115
URI
http://hdl.handle.net/10203/73253
Appears in Collection
NE-Journal Papers(저널논문)
Files in This Item
There are no files associated with this item.
  • Hit : 226
  • Download : 0
  • Cited 0 times in thomson ci
This item is cited by other documents in WoS
⊙ Detail Information in WoSⓡClick to seewebofscience_button
⊙ Cited 25 items in WoSClick to see citing articles inrecords_button

qr_code

  • mendeley

    citeulike


rss_1.0 rss_2.0 atom_1.0