Transformation zone shape, size, and crack-growth-resistance (R-curve) behavior of ceria-partially-stabilized zirconia polycrystals

Technical Report · Thu Jun 01 04:00:00 EDT 1989

OSTI ID:5247785

Yu, C S; Shetty, D K

Transformation-zone shape, size, and crack-growth-resistance (R-curve) behavior were studied in precracked and annealed single-edge notch-bend specimens of commercial-grade ceria-partially-stabilized zirconia polycrystals as a function of applied load. Well-defined transformations zoned with a characteristic elongated shape in the plane of the crack were observed, It is shown that the observed zone shape is significantly different from the shape predicted by a combined shear/dilation yield criterion and the stress field of the crack prior to the transformation. The length of the transformation zone directly ahead of the crack tip is in better agreement with the prediction of the Dugdale plastic strip-zone model. The fracture-toughness increment showed the characteristic square root dependence on the transformation zone width, but the magnitude of the toughness increment was not consistent with the predictions of the theoretical models of transformation toughening.

• Research Organization: Utah Univ., Salt Lake City, UT (USA). Dept. of Materials Science and Engineering
• OSTI ID: 5247785
• Report Number(s): AD-A-212020/2/XAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
CERAMICS
CERIUM COMPOUNDS
CERIUM OXIDES
CHALCOGENIDES
CRACK PROPAGATION
CRACKS
CRYSTAL STRUCTURE
CRYSTALS
DIMENSIONS
FRACTURE PROPERTIES
MECHANICAL PROPERTIES
METALLURGICAL EFFECTS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PLASTICITY
POLYCRYSTALS
RARE EARTH COMPOUNDS
SHAPE
STABILIZATION
STRESSES
TRANSITION ELEMENT COMPOUNDS
WIDTH
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES