Erosion Damage in Zirconia and Zirconia Toughened Alumina

During the last decade it has been unequivocally established that the stress induced transformation of zirconia from the tetragonal to monoclinic phase can substantially enhance the fracture toughness and strength of zirconia, as well as other ceramics containing zirconia as a second phase (1,2,3). It would be expected that these transformation toughened zirconia materials would also exhibit superior resistance to impact damage. However, relatively few studies (4,5,6] have been performed to validate this superposition.Therefore , the purpose of this research was to evaluate sharp particle impact damage in tetragonal zirconia polycrystals (TZP) and zirconia toughened alumna (ZTA). For this purpose, samples were subjected to multi-particle impact and the impact damage was characterized in terms of erosive wear and strength degradation.