Creep Damage Mechanisms in Hot-Pressed Alumina

The creep fracture behaviour of two commercially available hot-pressed aluminas has been extensively studied, both in flexure and tension. Three distinct regions are observed. At high stress, failure is by slow crack growth, dominated by a single flaw. At intermediate stresses, widely distributed microcracking is observed. Microcrack linkage differs for flexure and tension, resulting in large increases in lifteime for the flexure geometry. At …