Radiation hardening and radiation-anneal hardening in vanadium--oxygen alloys

Conference · Mon Jan 01 04:00:00 EST 1973

OSTI ID:4420853

Wechsler, M S; Alexander, D G; Bajaj, R; Carlson, O N

>From conference on defects and defect clusters in bcc metals and their alloys; Gaithersburg, Maryland, USA (14 Aug 1973). Tensile tests were performed on high-purity vanadium containing 60 to 3160 weight ppM oxygen. Portions were irradiated to 1.2 x 10/sup 19/ neutrons/cm/sup 2/ (E>1 MeV at 105 deg C and to 1.5 x 10/sup 19/ y of radiation-anneal hardening (RAH) in which the additional hardening upon post-irradiation annealing between 100 and 800 deg C was observed, as well as the recovery to pre-irradiation properties, and (2) the effect of irradiation on the temperature dependence of yielding in unirradiated, as- irradiated, and radiation-annealed specimens. The RAH (yield stress increase) occurs over the annealing temperature range of 100 to 4O0 deg C, and appears to increase in magnitude with increasing oxygen concentration. Recovery to pre- irradiation yield stress values takes place at 500 to 700 deg C. The mechanism proposed is that interstitial oxygen migrates to radiation-produced defect clusters, thus strengthening them as barriers to slip dislocation motion. The temperature dependence of the yield stress was observed over the range of test temperatures from 4 to 40O deg K. Radiation hardening increased with increasing oxygen concentrations for tests at 195 to 40O deg K. This was interpreted tentatively in terms of the formation of stronger dispersed barriers for higher oxygen alloys due to some trapping of oxygen at defect clusters during irradiation. At 4 and 77 deg K, where twinning occurs, the radiation hardening dirminished with increasing oxygen concentration. Radiation softening did not occur, when analyzed in terms of the total yield stress. (10 figures, 44 references) (auth)

• Research Organization: Iowa State Univ. of Science and Technology, Ames (USA)
• NSA Number: NSA-29-003098
• OSTI ID: 4420853
• Report Number(s): IS--3182; CONF-730813--10
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

*OXYGEN ADDITIONS
*VANADIUM BASE ALLOYS-- RADIATION HARDENING
ANNEALING
CHEMICAL COMPOSITION
FAST NEUTRONS
N50240* --Metals
Ceramics
& Other Materials--Metals & Alloys--Radiation Effects
NEUTRON BEAMS
QUANTITY RATIO
TEMPERATURE DEPENDENCE