Fracture-mechanics behavior of neutron-irradiated Alloy A-286

Conference · Fri Jul 01 04:00:00 EDT 1983

OSTI ID:5558552

Mills, W J; James, L A

The effect of fast-neutron irradiation on the fatigue-crack propagation and fracture toughness behavior of Alloy A-286 was characterized using fracture mechanics techniques. The fracture toughness was found to decrease continuously with increasing irradiation damage at both 24/sup 0/C and 427/sup 0/C. In the unirradiated and low fluence conditions, specimens displayed appreciable plasticity prior to fracture, and equivalent K/sub Ic/ values were determined from J/sub Ic/ fracture toughness results. At high irradiation exposure levels, specimens exhibited a brittle K/sub Ic/ fracture mode. The 427/sup 0/C fracture toughness fell from 129 MPa..sqrt..m in the unirradiated condition to 35 MPa..sqrt..m at an exposure of 16.2 dpa (total fluence of 5.2 x 10/sup 22/ n/cm/sup 2/). Room temperature fracture toughness values were consistently 40 to 60% higher than the 427/sup 0/C values. Electron fractography revealed that the reduction in fracture resistance was attributed to a fracture mechanism transition from ductile microvoid coalescence to channel fracture. Fatigue-crack propagation tests were conducted at 427/sup 0/C on specimens irradiated at 2.4 dpa and 16.2 dpa. Crack growth rates at the lower exposure level were comparable to those in unirradiated material, while those at the higher exposure were slightly higher than in unirradiated material.

• Research Organization: Hanford Engineering Development Lab., Richland, WA (USA)
• DOE Contract Number: AC06-76FF02170
• OSTI ID: 5558552
• Report Number(s): HEDL-SA-2982; CONF-8310198-1; ON: DE84001467
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360106* -- Metals & Alloys-- Radiation Effects
ALLOY-A-286
ALLOYS
ALUMINIUM ADDITIONS
ALUMINIUM ALLOYS
CHROMIUM ALLOYS
CRACK PROPAGATION
FATIGUE
FRACTOGRAPHY
FRACTURE MECHANICS
FRACTURE PROPERTIES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
HIGH TEMPERATURE
MATERIALS
MECHANICAL PROPERTIES
MECHANICS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
TITANIUM ALLOYS