| 摘要 |
PROBLEM TO BE SOLVED: To provide alumina ceramics with a theoretical density of 98% or more, preferably 99% or more, by firing at a relatively low firing temperature after compounding a small amount of specific γ-alumina ultrafine particles into an alumina ceramic raw material with a main component of α-alumina particles. SOLUTION: In manufacturing alumina ceramics, γ-alumina ultrafine particles consisting of spherical single particles with an averaged particle size of 20-80 nm and a BET specific surface area of 20-90 m2 are compounded in 0.5-5.0 weight % into an alumina ceramic raw material with a main component of α-alumina particles, and then the compounded material is fired. |
