Strength Improvement of Yttria‐Partially‐Stabilized Zirconia by Flaw Elimination

A systematic improvement of the flexural strength of conventionally sintered 4.5-wt%-Y2O3-partially-stabilized zirconia was realized by identifying the fracture origins of four-point-bend bars and eliminating them by process modification. The average flexural strength increased from 880 to 1380 MPa, a value comparable with that of isostatically hot-pressed or slip-cast material. A part-through crack extension model was used to correlate the fracture stresses and the fracture origin sizes and a “fracture origin severity parameter” was identified.

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