Effects of irradiation on initiation and crack-arrest toughness of two high-copper welds and on stainless steel cladding

Conference · Mon Jan 01 04:00:00 EST 1990

OSTI ID:6464107

Nanstad, R K; Iskander, S K; Haggag, F M

The objective of the study on the high-copper welds is to determine the effect of neutron irradiation on the shift and shape of the ASME K{sub Ic} and K{sub Ia} toughness curves. Two submerged-arc welds with copper contents of 0.23 and 0.31 wt % were commercially fabricated in 220-mm-thick plate. Compact specimens fabricated from these welds were irradiated at a nominal temperature of 288{degree}C to fluences from 1.5 to 1.9 {times} 10{sup 19} neutrons/cm{sup 2} (>1 MeV). The fracture toughness test results show that the irradiation-induced shifts at 100 MPa/m were greater than the Charpy 41-J shifts by about 11 and 18{degree}C. Mean curve fits indicate mixed results regarding curve shape changes, but curves constructed as lower boundaries to the data do indicate curves of lower slopes. A preliminary evaluation of the crack-arrest results shows that the neutron-irradiation induced crack-arrest toughness temperature shift is about the same as the Charpy V-notch impact temperature shift at the 41-J energy level. The shape of the lower bound curves (for the range of test temperatures covered), compared to those of the ASME K{sub Ia} curve did not appear to have been altered by the irradiation. Three-wire stainless steel weld overlay cladding was irradiated at 288{degree}C to fluences of 2 and 5 {times} 10{sup 19} neutrons/cm{sup 2} (>1 MeV). Charpy 41-J temperature shifts of 13 and 28{degree}C were observed, respectively. For the lower fluence only, 12.7-mm thick compact specimens showed decreases in both J{sub Ic} and the tearing modulus. Comparison of the fracture toughness results with typical plate and a low upper-shelf weld reveals that the irradiated stainless steel cladding possesses low ductile initiation fracture toughness comparable to the low upper-shelf weld. 8 refs., 12 figs., 2 tabs.

• Research Organization: Oak Ridge National Lab., TN (USA)
• Sponsoring Organization: NRC
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6464107
• Report Number(s): CONF-9010217-1; ON: DE91001272
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
220700* -- Nuclear Reactor Technology-- Plutonium & Isotope Production Reactors
36 MATERIALS SCIENCE
360103 -- Metals & Alloys-- Mechanical Properties
360106 -- Metals & Alloys-- Radiation Effects
ALLOYS
CONTAINERS
COPPER
ELEMENTS
FRACTURE MECHANICS
HIGH ALLOY STEELS
IRON ALLOYS
IRON BASE ALLOYS
IRRADIATION
JOINTS
MECHANICAL PROPERTIES
MECHANICS
METALS
PRESSURE VESSELS
RADIATION EFFECTS
STAINLESS STEELS
STEELS
TRANSITION ELEMENTS
WELDED JOINTS