COMPUTER-AIDED, SINGLE-SPECIMEN CONTROLLED BENDING TEST FOR FRACTURE-KINETICS MEASUREMENT IN CERAMICS

Fracture testing of ceramics by using controlled crack growth is propo sed to allow study of crack-kinetics behavior under a given loading hi story, A computer-aided, real-time data acquisition system improves th e quality of crack-growth parameters obtained in a simple, single-spec imen bend test, Several ceramic materials were tested in the present s tudy: aluminum nitride as a linear-elastic material; and alumina and y ttria-stabilized zirconia, both representative of ceramics with micros tructure-dependent nonlinear fracture properties, Ambiguities in the c rack-growth diagrams are discussed to show the importance of accountin g for crack-growth history in correctly describing nonequilibrium frac ture behavior.