High-strength transparent zirconia sintered body, process for producing the same, and uses thereof

Patent metadata

Field	Value
Publication number	US-9249058-B2
Application number	US-201414168651-A
Country	US
Kind code	B2
Filing date	Jan 30, 2014
Priority date	Jun 4, 2009
Publication date	Feb 2, 2016
Grant date	Feb 2, 2016

Abstract

Translucent zirconia sintered bodies have had a problem that incorporation of titania improves translucency but lowers mechanical strength. The invention provides: a zirconia sintered body containing titanium oxide, the sintered body containing 6-15 mol % yttria and 3-20 mol % titania and having an in-line transmission of 50% or higher when examined at a sample thickness of 1 mm and a measuring wavelength of 600 nm; and a zirconia sintered body having especially high translucency which is a high-quality transparent zirconia sintered body that contains 3-20 mol % titania and 6-15 mol % yttria and has an in-line transmission, as measured at a wavelength of 600 nm, of 73% or higher and a haze value of 2.0% or less and that is highly translucent and is undimmed (cloudless). The invention further relates to a production process in which a powder having the composition is molded and thereafter subjected to ordinary-pressure primary sintering and hot isostatic pressing (HIP) under specific conditions.

First claim

The invention claimed is:

1. A zirconia sintered body comprising yttria in an amount of 6-15 mol % and titania in an amount of 3-20 mol %, the zirconia sintered body having an average grain size of less than 30 μm, an in-line transmission of 50% or higher when examined at a sample thickness of 1 mm and a measuring wavelength of 600 nm, a total forward transmission of 71.9% or higher when examined at a sample thickness of 1 mm and a measuring wavelength of 600 nm, a sinter density of 99.9% or higher, and a crystalline phase, the crystalline phase having a cubic fluorite structure.

2. The zirconia sintered body as claimed in claim 1 having an average bending strength of 250 MPa or higher.

3. An optical part which comprises the zirconia sintered body as claimed in claim 1 .

4. The optical part as claimed in claim 3 which comprises an optical lens.

5. An exterior part for electronic appliances which comprises the zirconia sintered body as claimed in claim 1 .

Assignees

• Yamashita Isao
• Kudou Masayuki
• Tsukuma Koji
• Tosoh Corp

Inventors

• Yamashita Isao
• Kudou Masayuki
• Tsukuma Koji

Classifications

• G02B1/02

  made of crystals, e.g. rock-salt, semi-conductors (G02B1/08 takes precedence) · CPC title

• C04B2235/9623

  Ceramic setters properties · CPC title

• C04B2235/3225

  Yttrium oxide or oxide-forming salts thereof · CPC title

• C04B2235/3246

  Stabilised zirconias, e.g. YSZ or cerium stabilised zirconia · CPC title

• C04B2235/9646

  Optical properties · CPC title