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Effect of Lateral Cracks Upon Fracture Toughness Determined by the Surface Crack in Flexure Method
Published
Author(s)
George D. Quinn, J A. Salem
Abstract
The surface crack in flexure method uses a Knoop indenter to create small semi elliptical surface pre cracks in beam specimens. Lateral cracks may interfere with and cause errors in measurements of fracture toughness particularly for materials whose fracture toughness is 3. Mpa{root} of less. The residual stress damage zone is hand ground or polished away after indentation, but the customary amounts may not be sufficient to eliminate lateral cracks in very brittle materials. A simple remedy to detect and solve the problem is described.
Quinn, G.
and Salem, J.
(2002),
Effect of Lateral Cracks Upon Fracture Toughness Determined by the Surface Crack in Flexure Method, Journal of the American Ceramic Society
(Accessed October 21, 2025)