Rare-Earth Oxide-Doped Magnesium Aluminate Spinel - an Overview

Abstract

Abstract: Magnesium aluminate spinel (MAS) is an important refractory material known for its high refractoriness, high thermal shock resistance, high-temperature mechanical and thermal properties, high resistance to chemical attack, superior hydration resistance, etc. MAS has been employed to replace traditional chromite-based refractories in cement rotary kilns and steel ladles because chromite based refractories pose environmental issues. Thin films of MAS have potential use in thermal barrier coatings (TBCs) for the blades and vanes in the hot section components of gas turbines. Rare-earth oxide dopants play a significant role in the formation and sintering of MAS. Research has shown that the microstructure of MAS can be tailored with the help of rare-earth dopants, leading to a significant improvement in their sintering behaviour and mechanical properties. This review paper attempts to present the sintering aspects, and the mechanical and thermo-mechanical behaviour of rare-earth oxide-doped MAS.