ALUMINA SINTERED BODY

PROBLEM TO BE SOLVED : To provide an alumina sintered body having improved strength at room temperature and at high temperature as well as increased hardness without damaging chemical stability. SOLUTION : The alumina sintered body essentially comprises Al2O3 grains and contains at least one kind of compound selected from compounds expressed by RE2Ti2O7 (wherein RE represents a rare earth element) in a granular state (a dispersion phase) in the Al2O3 grains. The granules (dispersion phase) further contain MgAl2O4. The sintered body contains RE2Ti2O7 and MgAl2O4 in total by ≥0.5 vol.%. The average particle size of the granules (dispersion phase) is preferably ≤0.3 μm.