Used as an abrasive in grinding and polishing due to its hardness, especially in sandpapers and cutting tools. Commonly employed as a catalyst support in chemical reactions because of its high surface area and thermal stability, including as a carrier in industrial processes like oil refining. Serves as a refractory material in linings of furnaces and kilns and in ceramics for high-temperature strength and electrical insulation, owing to its ability to withstand high temperatures. Key intermediate in aluminum production via electrolysis processes like the Hall-Héroult method. Applied as a protective coating through thermal spraying to enhance wear and corrosion resistance of metal surfaces. Utilized in electronics as a dielectric material in integrated circuits and as a substrate for semiconductor devices, valued for good thermal conductivity without electrical conductivity. Found in medical applications, such as in prosthetic implants and device coatings, due to its biocompatibility and wear resistance. Also used in chromatography as a stationary phase for separating polar compounds.