Red zirconia sintered body and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-10550040-B2
Application number	US-201615749336-A
Country	US
Kind code	B2
Filing date	Sep 1, 2016
Priority date	Sep 3, 2015
Publication date	Feb 4, 2020
Grant date	Feb 4, 2020

Abstract

Provided is a zirconia sintered body that uses coloring of cerium oxide, the zirconia sintered body exhibiting a bright red color. The zirconia sintered body includes an oxide of cerium is an amount of 0.5% by mole or more and less than 4% by mole in terms of CeO 2 , yttria in an amount of 2% by mole or more and less than 6% by mole, an oxide of aluminum in an amount of 0.1% by weight or more and less than 2% by weight, and the balance being zirconia. The oxide of cerium contains trivalent cerium, and the zirconia has a crystal structure including a tetragonal phase.

First claim

The invention claimed is:

1. A red color zirconia sintered body comprising an oxide of cerium in an amount of 0.5% by mole or more and less than 4% by mole in terms of CeO 2 ; yttria in an amount of 2% by mole or more and less than 6% by mole; an oxide of aluminum in an amount of 0.1% by weight or more and less than 2% by weight; and the balance being zirconia,
wherein the oxide of cerium contains trivalent cerium, and the zirconia has a crystal structure including a tetragonal crystal; and
wherein a lightness L* is 20 or more, a hue a* is 30 or more, and a ratio of the hue a* to a hue b* satisfies 0.9≤a*/b*, in an L*a*b* color system.

2. The red color zirconia sintered body according to claim 1 , wherein the oxide of aluminum comprises at least one selected from the group consisting of spinel (MgAl 2 O 4 ), lanthanum aluminate (LaAl 11 O 19 ), and aluminum oxide.

3. The red color zirconia sintered body according to claim 1 , wherein crystal grains of zirconia have an average crystal grain size of 2 μm or less.

4. A method for manufacturing the red color zirconia sintered body according to claim 1 , the method comprising sintering, in a reducing atmosphere, a compact containing yttria in an amount of 2% by mole or more and less than 6% by mole, an oxide of cerium in an amount of 0.5% by mole or more and less than 4% by mole in terms of CeO 2 , an oxide of aluminum in an amount of 0.1% by weight or more and less than 2% by weight, and the balance being zirconia.

5. The manufacturing method according to claim 4 , wherein the sintering includes a primary sintering subjecting the compact to pressureless sintering to obtain a primary sintered body, and a secondary sintering subjecting the primary sintered body to hot isostatic pressing.

6. The manufacturing method according to claim 4 , wherein the sintering includes a primary sintering subjecting the compact to pressureless sintering in an oxidizing atmosphere to obtain a primary sintered body, and a secondary sintering subjecting the primary sintered body to pressureless sintering in a reducing atmosphere.

7. A member comprising the red color zirconia sintered body according to claim 1 .

8. A zirconia complex sintered body comprising the red color zirconia sintered body according to claim 1 and a zirconia sintered body containing at least one element selected from the group consisting of Al, Ti, Pr, Nd, Eu, Tb, Ho, Er, Yb, and Gd.

Assignees

• Tosoh Corp

Inventors

• Yamauchi Shoichi
• Ito Takeshi
• Tsuchiya Satoshi

Classifications

• C04B2235/3206

  Magnesium oxides or oxide-forming salts thereof · CPC title

• C04B2235/3224

  Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide · CPC title

• C04B35/64

  Burning or sintering processes (C04B33/32 takes precedence {; powder metallurgy B22F}) · CPC title

• C04B2235/3232

  Titanium oxides or titanates, e.g. rutile or anatase · CPC title

• C04B2235/3225

  Yttrium oxide or oxide-forming salts thereof · CPC title