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

Journal Article · Thu Jun 01 04:00:00 EDT 1989 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1989.tb06245.x· OSTI ID:6170719

Yu, C S; Shetty, D K ^[1]

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1. Utah Univ., Salt Lake City, UT (United States). Dept. of Materials Science and Engineering

This paper reports on transformation zone shape, size, and crack-growth-resistance behavior 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 transformation zones 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/dilatation 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 mode. 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.

• OSTI ID: 6170719
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 72:6; ISSN JACTA; ISSN 0002-7820
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202 -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360203* -- Ceramics
Cermets
& Refractories-- Mechanical Properties
CHALCOGENIDES
CRACK PROPAGATION
CRYSTALS
HARDNESS
MECHANICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
POLYCRYSTALS
SHAPE
SIZE
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES