Fractography in Materials Research

The manner in which the crack interacts with the microstructure of a ceramic can affect both the fracture toughness and the strength. In composite ceramics such as those with SiC fibers in an AI2O3 matrix, for example, the highest toughness is obtained when the bond between the fibers and the matrix is weak enough that the fibers pull out of the matrix rather than fail when the crack front intersects them. It should be obvious that examination of the fracture surface can provide information on the failure mode and, thus, aid in the optimization of the toughness. 

Lawn and T. R. Wilshaw. Fracture of Brittle Solids. Cambridge University Press, Cambridge, 1975. 

Inglis. Stresses in a Plate Due to the Presence of Cracks and Sharp Corners. Trans. Inst. Navla Archit. 55, 219, 1913. 

Orowan. Energy Criteria of Fracture. Weld. Res. Supp. 34, 157, 1958. 

Lawn and D. B. Marshall. Indentation Fracture and Strength Degradation in Ceramics. Fracture Mechanics of Ceramics, Vol. 3. Plenum, 1978, p. 205. 

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