Ion bombardment damage in a modified Fe-9Cr-1Mo steel

Conference · Sun Jan 01 04:00:00 EST 1984

OSTI ID:6788676

Farrell, K; Lee, E H

A normalized-and-tempered Fe-9Cr-1Mo steel, with small Nb and V additions, was bombarded with 4-MeV iron ions to 100 dpa at 400, 450, 500, 550, and 600/sup 0/C. Major damage feature was dislocation tangles which coarsened with increasing bombardment temperature. Sparse cavities were heterogeneously distributed at 500 and 550/sup 0/C. Incorporation of helium and deuterium simultaneously in the bombardments at rates of 10 and 45 appM/dpa, respectively, introduced very high concentrations of small cavities at all temperatures, many of them on grain boundaries. These cavities were shown to be promoted by helium. A small fraction of the matrix cavities exhibited bias-driven growth at 500 and 550/sup 0/C, with swelling <0.4%. This is a very narrow temperature range for bias-driven swelling. It is about 125/sup 0/C higher than the peak swelling temperature found in neutron irradiations, which is compatible with the higher damage rate used in the ion bombardments. High concentrations of subgrain boundaries and dislocations resulting from the heat treatment, and unbalanced cavity and dislocation sink strengths in the damage structures contribute to the swelling resistance. Such resistance may not be permanent. High densities of bubbles on grain boundaries indicate a need for helium embrittlement tests.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6788676
• Report Number(s): CONF-840604-10; ON: DE84014288
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360106* -- Metals &amp; Alloys-- Radiation Effects
ALLOYS
BEAMS
CHARGED PARTICLES
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-MOLYBDENUM STEELS
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DISLOCATIONS
ELEMENTS
ENERGY RANGE
FERRITIC STEELS
FLUIDS
GASES
HELIUM
HIGH TEMPERATURE
ION BEAMS
IONS
IRON ALLOYS
IRON BASE ALLOYS
IRON IONS
LINE DEFECTS
MEV RANGE
MEV RANGE 01-10
MICROSTRUCTURE
NONMETALS
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
RARE GASES
STEELS
SWELLING
TEMPERATURE DEPENDENCE