Indentation Contact Deformation of 3Y-TZP at Elevated Temperatures
The contact deformation mechanisms of a superplastic ceramic, 3Y-TZP (3mol % yttria-partially stabilized tetragonal zirconia polycrystals) are examined in indentation creep tests at high temperatures. A large discrepancy between the uniaxial compression and the pyramidal indentation contact behaviors is observed. The indentation creep curves exhibit a hardening behavior, i.e., the penetration rate decreases as the penetration depth and/or the creep time increases. This fact implied that the cooperative grain-boundary sliding (CGBS) in a microscopically localized region, such as the sub-surface contact region beneath a pyramidal indenter, is very limited through the microscopic processes of localized grain interlocking.
T. Ohji, T. Sekino and K. Niihara
H. Muto et al., "Indentation Contact Deformation of 3Y-TZP at Elevated Temperatures", Key Engineering Materials, Vols. 317-318, pp. 469-472, 2006