Subcritical crack growth in zirconia-toughened alumina (ZTA) ceramics

A study of subcritical crack growth in zirconia-toughened alumina (ZTA) ceramics was carried. The Al2O3–10 wt% ZrO2 ceramics containing two types of ZrO2 particles: 3 mol% yttria stabilized ZrO2 and pure ZrO2 were tested. For comparison, the alumina ceramics was included to examination. The load–relaxation technique was used for observation subcritical crack growth. The crack length was evaluated by linear-elastic analysis from the compliance of single-edge-notched specimen in three-point bending test. Parameters n, log A, work-of-fracture (WOF), stress intensity factor at the moment of crack initiation KI(i) and maximum values of stress intensity factor KI(max) were determined.