Damage accumulation caused by cyclic indentation in zirconia ceramics

Indentation fatigue testing is carried out for four kinds of zirconia ceram ics; 6Y-FSZ, 3Y-TZP, Mg-PSZ and Ce-TZP; which have different strengthening- toughening mechanisms one another. Each material shows different indentatio n fatigue behavior. Large sized surface chipping is produced easily in earl y cycles for non-toughened 6Y-FSZ, while 3Y-TZP toughened by anelasticity h as high resistance against chipping. There is a possibility that anelastic characteristic works as resistance against indentation fatigue damage. Stre ss induced phase transformation also improves fatigue damage, but this effe ct depends on the extent of transformation and/or occurrence of microcracki ng. (C) 1999 Kluwer Academic Publishers.