Back to results
US 6,306,788 B1Granted
Translucent alumina sintered body and production thereof
AssigneeSumitomo Chemical Company, Limited
InventorsHisashi Watanabe, Yoshio Uchida
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeSumitomo Chemical Company, Limited
InventorsHisashi Watanabe, Yoshio Uchida
Estimating the term…
A method for producing a translucent alumina sintered body comprising the steps of: forming a raw material powder, and sintering the formed product under the condition of hydrogen atmosphere from atmospheric pressure to vacuum at a temperature of from 1600 to 1900° C., wherein the raw material powder is a mixed powder comprising an α-alumina powder (1) which comprises a polyhedral primary particle having substantially no fractured surface, has a BET specific surface area of 1 to 7 m2/g, and has a purity of 99.99% or more, an alumina powder (2) having a BET specific surface area of 5 to 200 m2/g in an amount of 10% by weight or less based on said α-alumina powder, and a sintering agent, and satisfies the following formula: (BET specific surface area of alumina powder (2))−(BET specific surface area of α-alumina powder (1))>2 m2/g.
A method for producing a translucent alumina sintered body comprising the steps of:
A translucent alumina sintered body having an average grain size of 20 to 50 μm, and having linear transmittance of light of from 50 to 70%, when light having a wavelength of 600 nm is passed through a plate of the sintered body having a thickness of 0.85 mm.
Dependencies are inferred from the claim text.