IP Library Granted Patent US 11,667,574
Granted Patent B2
US 11,667,574 · App. 16/768,231 · Granted Jun 6, 2023

Precursor of alumina sintered body, method for producing alumina sintered body, method for producing abrasive grains, and alumina sintered body

Inventors: So Miyaishi (Kawasaki, JP); Satoshi Iinou (Matsumoto, JP)
Assignee: SHOWA DENKO K.K.
C04B35/10C09K3/1418C04B2235/3225C04B2235/404C04B2235/405C04B2235/407C04B2235/408
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Quick Facts
Patent No.
US 11,667,574
App. No.
16/768,231
Granted
Jun 6, 2023
Kind
B2
Abstract

A precursor of an alumina sintered compact including aluminum, yttrium, and at least one metal selected from iron, zinc, cobalt, manganese, copper, niobium, antimony, tungsten, silver, and gallium. The aluminum content is 98.0% by mass or more as an oxide (Al 2 O 3 ) in 100% by mass of the precursor of an alumina sintered compact; the yttrium content is 0.01 to 1.35 parts by mass as an oxide (Y 2 O 3 ) based on 100 parts by mass of the content of the aluminum as an oxide; the total content of the metals selected from the foregoing group is 0.02 to 1.55 parts by mass as an oxide based on 100 parts by mass of the content of aluminum as an oxide; and the aluminum is contained as α-alumina. Also disclosed is an alumina sintered compact, and a method for producing an alumina sintered compact and for producing abrasive grains.

Claims (21)

1. A precursor of an alumina sintered compact comprising aluminum, yttrium, silicon, and at least one metal selected from the group consisting of iron, zinc, cobalt, manganese, copper, niobium, antimony, tungsten, silver, and gallium, wherein

the content of the aluminum is 98.0% by mass or more as expressed in terms of an oxide (Al 2 O 3 ) in 100% by mass of the precursor of an alumina sintered compact;

the content of the yttrium is 0.01 to 1.35 parts by mass as expressed in terms of an oxide (Y 2 O 3 ) based on 100 parts by mass of the content of the aluminum as expressed in terms of an oxide;

the total content of the metals selected from the foregoing group is 0.02 to 1.55 parts by mass as expressed in terms of an oxide based on 100 parts by mass of the content of aluminum as expressed in terms of an oxide;

the aluminum is contained as α-alumina; and

the content of the silicon is 0.001 to 0.12 parts by mass as expressed in terms of an oxide (SiO 2 ) based on 100 parts by mass of the content of the aluminum as expressed in terms of the oxide (Al 2 O 3 ).

2. The precursor of an alumina sintered compact according to claim 1 , wherein the yttrium is contained as yttrium acetate tetrahydrate.

3. The precursor of an alumina sintered compact according to claim 1 , which is used for obtaining an alumina sintered compact constituting abrasive grains.

4. A method for producing an alumina sintered compact, comprising:

a step (I) of obtaining the precursor of an alumina sintered compact according to claim 1 ; and

a step (II) of firing the precursor of an alumina sintered compact, to obtain an alumina sintered compact.

5. The method for producing an alumina sintered compact according to claim 4 , wherein the step (I) of obtaining the precursor of an alumina sintered compact includes a step of mixing α-alumina, a compound containing yttrium, and a compound containing at least one metal selected from the group consisting of iron, zinc, cobalt, manganese, copper, niobium, antimony, tungsten, silver, and gallium.

6. The method for producing an alumina sintered compact according to claim 4 , wherein the compound containing yttrium is yttrium acetate tetrahydrate.

7. The method for producing an alumina sintered compact according to claim 4 , wherein a firing temperature of the precursor of an alumina sintered compact is 1,300 to 1,575° C.

8. The method for producing an alumina sintered compact according to claim 4 , wherein a relative density of the alumina sintered compact is 95.0% or more.

9. An alumina sintered compact comprising aluminum, yttrium, silicon, and at least one metal selected from the group consisting of iron, zinc, cobalt, manganese, copper, niobium, antimony, tungsten, silver, and gallium, wherein

the content of the aluminum is 98.0% by mass or more as expressed in terms of an oxide (Al 2 O 3 ) in 100% by mass of the alumina sintered compact;

the content of the yttrium is 0.01 to 1.35 parts by mass as expressed in terms of an oxide (Y 2 O 3 ) based on 100 parts by mass of the content of the aluminum as expressed in terms of an oxide;

the total content of the metals selected from the foregoing group is 0.02 to 1.55 parts by mass as expressed in terms of an oxide based on 100 parts by mass of the content of aluminum as expressed in terms of an oxide;

a relative density of the alumina sintered compact is 95.0% or more; and

the content of the silicon is 0.001 to 0.12 parts by mass as expressed in terms of an oxide (SiO 2 ) based on 100 parts by mass of the content of the aluminum as expressed in terms of an oxide (Al 2 O 3 ).

Assignments (2)
CHANGE OF NAME Recorded Jun 23, 2023
From: SHOWA DENKO K.K.
To: RESONAC CORPORATION
Reel/Frame 064082/0513 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 29, 2020
From: MIYAISHI, SO; IINOU, SATOSHI
To: SHOWA DENKO K.K.
Reel/Frame 052790/0285 →