Interaction of interstitial impurities with radiation-induced defects leading to improved elevated temperature mechanical properties of mild steel

Journal Article · Mon Oct 01 04:00:00 EDT 1984 · Nucl. Technol.; (United States)

OSTI ID:5959619

Murty, K L

Improvements in both the yield strength and ductility were noted in mild steel at elevated temperatures (greater than or equal to315 K) following neutron irradiation to 2 X 10/sup 22/ n/m/sup 2/, in contrast to hitherto observed radiation hardening and embrittlement. This beneficial effect was shown to be due to the interaction of interstitial impurities with radiation-produced defects resulting in reduced concentration of interstitial carbon and nitrogen in solution, and thus blue brittleness is suppressed following radiation exposure. Consequently, the energy absorbed by the irradiated material (a measure of toughness) improved at these temperatures. In the temperature range examined, namely from 300 to 550 K, Luders strain increased following neutron irradiation. While the Luders strain of unirradiated material exhibited a peatk at about 460 K due to dynamic strain aging, it decreased continuously with test temperature following neutron irradiation. Radiation exposure resulted in decreased rates of work hardening at all of the test temperatures. Peaks in the temperature dependence of the work-hardening parameter are noted for the unirradiated material in the serrated flow regime. Thermal recovery of radiation damage resulted in increased rates of work hardening at elevated temperatures.

• Research Organization: North Carolina State University, P.O. Box 7909, Raleigh, North Carolina 27695
• OSTI ID: 5959619
• Journal Information: Nucl. Technol.; (United States), Journal Name: Nucl. Technol.; (United States) Vol. 67:1; ISSN NUTYB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360106* -- Metals & Alloys-- Radiation Effects
ALLOYS
DAMAGING NEUTRON FLUENCE
DEFECTS
DESTRUCTIVE TESTING
DUCTILITY
HARDENING
HIGH TEMPERATURE
IMPURITIES
IRON ALLOYS
IRON BASE ALLOYS
IRRADIATION
MATERIALS TESTING
MECHANICAL PROPERTIES
NEUTRON FLUENCE
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
STEELS
STRAIN HARDENING
TEMPERATURE EFFECTS
TENSILE PROPERTIES
TESTING
YIELD STRENGTH