Microstructure and mechanical properties of quasi-eutectic Al2O3–Y3Al5O12–ZrO2 ternary composites rapidly solidified from melt

The formation, microstructure and mechanical properties of Al2O3–Y3Al5O12–ZrO2 composites rapidly solidified from melts is presented. The studied compositions were inside the eutectic line between the Al2O3–Y3Al5O12 binary eutectic and the ternary eutectic, inside the Al2O3–Y3Al5O12–ZrO2 region of the Al2O3–Y2O3–ZrO2 ternary oxide diagram. Composites showing an homogeneous structure and phase distribution could be obtained in spite of the high thermal residual stresses generated upon cooling. The three-phase composites obtained by melt quenching have interphase spacings in the sub-micron range, due to the rapid growth during quenching. The fracture toughness of the ternary composites was measured by Vickers indentation methods.