Ultrasonic testing of the fracture toughness of Zr-Nb pressure tubes

Book · Tue Dec 31 04:00:00 EST 1996

OSTI ID:418166

Moreau, A; Bussiere, J F ^[1]

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1. National Research Council of Canada, Boucherville, Quebec (Canada). Industrial Materials Inst.

Bulk elastic properties were measured, using ultrasound, in thickness and circumferential directions of 13 Zr-Nb pressure tubes samples from CANDU nuclear reactors in the hope of finding a nondestructive means to evaluate fracture toughness. The longitudinal wave velocity in the thickness direction are found especially sensitive to changes in the {alpha}-Zr single-crystal c axis orientation distribution. This is verified by comparing measured values to predictions based on neutron diffraction measurements of the crystallographic orientation distribution and on the single-crystal elastic constants of {alpha}-Zr. Moreover, those velocities most sensitive to texture correlate best with the crack growth toughness of the pressure tubes. This led to the discovery of a correlation between the degree of alignment of the crystallographic c axes along the tube circumferential direction and crack growth toughness. The better is the alignment, the lower is crack growth toughness. Because of the measurement simplicity, the ultrasonic technique could be developed into a rugged industrial sensor.

• OSTI ID: 418166
• Report Number(s): CONF-960706--; ISBN 0-7918-1769-5
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
36 MATERIALS SCIENCE
CANDU TYPE REACTORS
CRACK PROPAGATION
EXPERIMENTAL DATA
FRACTURE PROPERTIES
NIOBIUM ALLOYS
PRESSURE TUBES
THEORETICAL DATA
ULTRASONIC TESTING
ZIRCONIUM BASE ALLOYS