Ms. Kaliszewski et al., INDENTATION STUDIES ON Y2O3-STABILIZED ZRO2 .1. DEVELOPMENT OF INDENTATION-INDUCED CRACKS, Journal of the American Ceramic Society, 77(5), 1994, pp. 1185-1193
The development of Vickers indent-induced cracks with increasing inden
t load has been studied in two Y2O3-stabilized ZrO2 ceramics. Such cra
cks form as radial or Palmqvist cracks at low loads, assume ''kidney''
shapes at intermediate loads, and finally form median (half-penny) cr
acks at high loads. The plastic zone directly beneath the indent is un
cracked; a significant portion of the plasticity induced by indentatio
n occurs by martensitic transformation.