D. Basu et Bk. Sarkar, TOUGHNESS DETERMINATION OF ZIRCONIA-TOUGHENED ALUMINA CERAMICS FROM GROWTH OF INDENTATION-INDUCED CRACKS, Journal of materials research, 11(12), 1996, pp. 3057-3063
Short surface cracks were generated by Vickers indentation on the poli
shed surface of alumina and different zirconia toughened alumina (ZTA)
specimens, and their morphology was studied by serial sectioning. The
se cracks were grown in three-point bend tests under stepwise loading,
and variation of toughness with crack extension was plotted to graphi
cally separate the contributions from residual stress intensity and ap
plied stress intensity factors. The plateau toughness determined from
the intercept height of the crack extension plots exhibited an upward
trend with zirconia content up to 15 vol% ZrO2 addition in the composi
tion, which was proportional to the fraction of transformable tetragon
al grains contributing to transformation toughening.