Fractography is the means and methods for characterizing a fractured specimen or component. This includes the examination of fracture-exposed surfaces and the interpretation of the fracture markings as well as the examination and interpretation of crack patterns. This article describes the former of these two parts of fractography. It presents the techniques of fractography and explains fracture markings using glass and ceramic examples. The article also discusses the fracture modes in ceramics and provides examples of fracture origins.

Metal-framed polycarbonate (PC) ophthalmic lenses shattered from acetone solvent-induced cracking. The lenses exhibited primary and secondary cracks with solvent swelling and crazing. A laboratory accident splashed acetone onto the lenses. The metal frames gripped approximately two-thirds of the lenses' periphery and introduced an unevenly distributed force on the lenses. To prevent future failures, it was recommended to protect PC from service environments with solvents, such as acetone; or from marking pens, adhesives or soaps which contain undesirable solvents; and to not apply excessive stress on ophthalmic lenses in the form of working or residual stresses.