Addition of Al–Ti–C master alloys and diopside to improve the performance of alumina matrix ceramic materials

In the present work, Al–Ti–C master alloys and diopside are introduced in alumina matrix ceramic materials. Composites are fabricated by the technology of transient liquid phase sintering, during which new phases such as Al6Si2O13, AlN and CaO·6Al2O3 are produced by the chemical reactions taking place among alumina and the additives. The densification rate of the composites as a function of Al–Ti–C volume content is discussed. The hardness, the fracture toughness and the bending strength of the composites are tested. Meanwhile, the effects of additives on mechanical properties and fracture mechanism of alumina matrix ceramic materials are analyzed and discussed together with the refining performances of Al–Ti–C master alloys.