Unlock instant, AI-driven research and patent intelligence for your innovation.

Alumina sintered body and ground substrate for optical element

一种烧结体、氧化铝的技术，应用在光学元件、氧化铝/氢氧化铝、氧化铝/氢氧化物制备等方向，能够解决烧成温度低、限制透光性、推测没有充分取向等问题，达到高透光性的效果

Active Publication Date: 2017-08-01
NGK INSULATORS LTD
View PDF3 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In Patent Document 1, although a molded body obtained by using platy alumina powder as a part of the raw material is fired, the purity of alumina is as low as less than 99.9% by mass, and the firing temperature is as low as 1500 to 1750°C. , and fired under normal pressure, therefore, it is presumed that there is no sufficient orientation
It is well known that the alumina sintered body has optical anisotropy in the crystal structure, and in the case of polycrystalline alumina with low orientation, light transmission is limited

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Alumina sintered body and ground substrate for optical element
  • Alumina sintered body and ground substrate for optical element
  • Alumina sintered body and ground substrate for optical element

Examples

Experimental program
Comparison scheme
Effect test

experiment example 1

[0045] 1. Production of alumina sintered body

[0046] (1) Preparation of tabular alumina powder

[0047] The solvent is IPA (isopropanol), using 96 parts by mass of high-purity γ-alumina powder (TM-300D, manufactured by Daming Chemical Co., Ltd.), high-purity AlF 3 4 parts by mass of powder (manufactured by Kanto Chemical Co., Ltd., Deer Special Grade) and 0.17 parts by mass of high-purity α-alumina powder (TM-DAR, produced by Daimei Chemical Co., Ltd., D50=1 μm) as a seed crystal were mixed in a pot mill for 5 hours. The total mass ratio of impurity elements other than F, H, C, and S contained in the obtained mixed powder is 1000 ppm or less. 300 g of the obtained mixed powder was put into a sagger made of high-purity alumina with a purity of 99.5% by mass (volume 750 cm 3 ), a cover made of high-purity alumina with a purity of 99.5% by mass was covered, and heat treatment was performed at 900° C. for 3 hours in an air flow in an electric furnace. The flow rate of air i...

experiment example 2

[0079] In the production of the alumina sintered body, in the firing of 1. (3) of Experimental Example 1, HIP firing was performed instead of hot pressing, and then HIP firing was performed in the same manner as Experimental Example 1. An alumina sintered body is produced. Conditions for sintering at atmospheric pressure: keep at 1350°C for 4 hours. In addition, the conditions of HIP firing: Ar is used as the pressure medium, and the pressure is 185 MPa, and the temperature is maintained at 1800° C. for 2 hours. The properties of the above 2. (1) to (7) were determined for the obtained alumina sintered body. The results are shown in Table 1.

experiment example 3

[0081] When producing the alumina sintered body, in the tape casting molding of 1.(2) of Experimental Example 1, 1.5 parts by mass of tabular alumina powder and 98.5 parts by mass of fine granular alumina powder were used. An alumina sintered body was produced in the same manner. The properties of the above 2. (1) to (7) were determined for the obtained alumina sintered body. The results are shown in Table 1.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
particle diameteraaaaaaaaaa
particle diameteraaaaaaaaaa
particle diameteraaaaaaaaaa
Login to View More

Abstract

This alumina sintered body exhibits a c-plane orientation of 90% or higher when obtained by the Lotgering method using an X-ray diffraction profile in the range of 2[theta]=20-70 degrees when irradiating a plate surface with X-rays, has zero air holes when viewing a cross-section perpendicular to the plate surface by using a scanning electron microscope at a magnification of 5000 times, after polishing using an Ar+ ion beam and a shielding plate, and exhibits a total mass proportion of impurity elements other than Mg and C of 100 ppm or less. This alumina sintered body has high orientation, high density and high purity, and as a result, exhibits a higher translucency than does the prior art.

Description

technical field [0001] The present invention relates to an alumina sintered body and a base substrate for an optical element. Background technique [0002] Polycrystalline alumina (Al 2 o 3 ) sintered body. With regard to this polycrystalline alumina sintered body, it is well known that by controlling the microstructure, the crystallographic orientations of constituent particles can be aligned with specific orientations (orientation), thereby improving mechanical strength, thermal shock resistance, and corrosion resistance. This is because fracture toughness, dielectric constant, thermal conductivity, and thermal expansion coefficient have anisotropy due to crystal orientation. For example, Patent Document 1 discloses that an oriented alumina sintered body produced by using plate-shaped alumina powder as a part of the raw material exhibits excellent heat resistance and corrosion resistance. In Patent Document 1, although a molded body obtained by using platy alumina powd...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C04B35/115G02B1/00C01F7/02C01F7/30C01F7/441C01F7/442
CPCG02B1/00C01F7/441C01F7/442C01P2004/20C01P2004/54C01P2004/61C04B35/6268C04B35/645C04B2235/3206C04B2235/3208C04B2235/322C04B2235/3418C04B2235/425C04B2235/445C04B2235/5296C04B2235/5445C04B2235/604C04B2235/72C04B2235/77C04B2235/787C04B2235/9692C30B1/12C30B28/02C01P2006/80C04B35/6455C04B2235/3217C04B2235/5292C04B2235/5436C04B2235/6025C04B2235/6567C04B2235/721C30B1/10C30B29/20C04B35/115H01L33/0093C04B35/10C04B35/64C04B2235/963C04B2235/9646C01F7/02C01F7/30C01P2002/72C04B35/6303C04B35/632C04B35/6342C04B35/638C04B2235/612C04B2235/656C04B2235/725C04B2235/9653C30B1/04H01L33/28H01L33/32
Inventor 松岛洁渡边守道佐藤圭七泷努
Owner NGK INSULATORS LTD