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Fracture Toughness of Toughened Silicon Nitride by ASTM C 1421



George D. Quinn, J Swab, M J. Motyka


The fracture toughness of a commercial sintered reaction-bonded silicon nitride was measured by the three complementary test methods in ASTM C 1421. Precracks ranged from tiny artificial flaws introduced by Knoop indentation to millimeter long precracks in single-edge precracked beams. Although this material probably has a rising R-curve, the fracture values from the three methods were in good agreement.
Journal of the American Ceramic Society
No. 6


ASTM C 1421, chevron notch beam, fracture toughness, reference material, silicon nitride, silicon-edge precracked beam, surface crack in flexure


Quinn, G. , Swab, J. and Motyka, M. (2003), Fracture Toughness of Toughened Silicon Nitride by ASTM C 1421, Journal of the American Ceramic Society (Accessed July 17, 2024)


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Created June 1, 2003, Updated February 19, 2017