STABLE CRACK-GROWTH IN CERAMICS AT AMBIENT AND ELEVATED-TEMPERATURES

Quasi-static, stable crack propagation tests in ceramics are presented. The tests are performed using a recently developed technique in which the crack mouth opening displacement (CMOD) is continuously monitored during the test by means of a laser extensometer, and this signal is employed to control a servo-hydraulic testing machine. The advantages of such tests to characterize the fracture behavior of ceramics at high temperature are described, and the technique is used to study the fracture behavior of an ytria-partially stabilized zirconia ceramic at ambient and elevated temperatures.