IP Library › Granted Patent US 8,927,447
Granted Patent B2
US 8,927,447 · App. 14/348,651 · Granted Jan 6, 2015

Ceramic sintered body

Inventors: Jun Moteki (Inuyama, JP); Yusuke Katsu (Komaki, JP); Takeshi Mitsuoka (Konan, JP)
Assignee: NGK Spark Plug Co., Ltd.
C04B35/106C04B35/119C04B35/5626C04B35/645B23B2226/18C04B2235/3217C04B2235/3225C04B2235/3246C04B2235/3843C04B2235/3847C04B2235/3856C04B2235/3886C04B2235/5436C04B2235/5445C04B2235/6562C04B2235/72C04B2235/85C04B2235/96C04B2235/9607
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Quick Facts
Patent No.
US 8,927,447
App. No.
14/348,651
Granted
Jan 6, 2015
Kind
B2
Abstract

A ceramic sintered body includes tungsten carbide, zirconia, and alumina. The content of the tungsten carbide is 20 to 50 vol %, and the content of the zirconia is 5 to 25 vol %. The crystal phase of the zirconia is a tetragonal crystal or a mixture of tetragonal and monoclinic crystals. The ceramic sintered body does not substantially include Ti compounds. The average particle diameter of the tungsten carbide, the average particle diameter of the zirconia, and the average particle diameter of the alumina are all 1 μm or less.

Claims (11)

1. A ceramic sintered body comprising:

tungsten carbide, zirconia, and alumina,

wherein the content of the tungsten carbide is 20 to 50 vol %,

wherein the content of the zirconia is 5 to 25 vol %,

wherein a crystal phase of the zirconia is a tetragonal crystal or a mixture of tetragonal and monoclinic crystals,

wherein the ceramic sintered body does not substantially include Ti compounds, and

wherein an average particle diameter of the tungsten carbide, an average particle diameter of the zirconia, and an average particle diameter of the alumina are all 1 μm or less.

2. The ceramic sintered body according to claim 1 ,

wherein the average particle diameter of the tungsten carbide is 0.7 μm or less.

3. The ceramic sintered body according to claim 1 ,

wherein a zirconium element is distributed in grain boundaries between the alumina and the tungsten carbide.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 13, 2023
From: NGK SPARK PLUG CO., LTD.
To: NTK CUTTING TOOLS CO., LTD.
Reel/Frame 063935/0018 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 31, 2014
From: MOTEKI, JUN; KATSU, YUSUKE; MITSUOKA, TAKESHI
To: NGK SPARK PLUG CO., LTD.
Reel/Frame 032563/0570 →
Priority Claims (1)
JP 2012-145676 · Jun 28, 2012 · national
Continuity (1)
Related Publication 20140242383A1 · Aug 28, 2014