Evolution of Structure in Sintering Ceramics Based on Aluminum Oxide with a Eutectic Additive

The aspects of sintering of corundum-based ceramics with a eutectic additive of the MnO – Al₂O₃ – SiO₂ system are considered in the context of the evolution of its structure. In sintering in the presence of a small quantity of eutectic, the behavior of the system is largely different before and after the emergence of the liquid phase. Before the liquid phase formation, the process is determined by the properties of the material located at the site of contact between the particles, and afterwards the system becomes sensitive to the state of the surface of the contact between the solid phase and the eutectic liquid. The latter is due to the fact that the eutectic composition is virtually saturated with respect to aluminum oxide.