Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Preparation method of pyrochlore-type A2B2O7 transparent ceramics

A technology of A2B2O7 and transparent ceramics, which is applied in the field of ceramic preparation, can solve the problems of low degree of crystallization and obstacles to application, and achieve high sintering activity, easy operation, and simple process flow

Inactive Publication Date: 2013-05-22
FUJIAN CASTECH CRYSTALS
View PDF4 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] The above five methods have all obtained pyrochlore-type A2B2O7 series compound powder or ceramics, but the degree of crystallization is not high, which hinders the application in some aspects, such as Tb2Ti2O7 used in magneto-optical materials, Dy2Ti2O7 and Ho2Ti2O7 are highly Frustrated spin-ice materials

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] Embodiment one : Weigh Tb according to the stoichiometric ratio of Tb2Ti2O7 4 o 7 and TiCl4, use 1:1 nitric acid to dissolve them into a solution and remove excess acid, while adding 10% ammonium sulfate and 0.5% PAA of the total molar amount of metal ions as a dispersant; use deionized ammonium bicarbonate Water is made into a solution, ammonium bicarbonate is 8 times the total molar weight of metal ions, and the volume is 3 times the volume of the mixed solution of metal ions, and it is completely dissolved; by reverse titration, at room temperature, the prepared The solution was slowly added dropwise to the ammonium bicarbonate at a speed of ≤10ml / min, and stirred. The precursor produced by reverse titration is flocculent and has a large specific surface area. Due to the addition of ammonium sulfate and PAA as a dispersant, this precursor can obtain particles with less agglomeration after calcination and has a higher specific surface area. Active, conducive to the...

Embodiment 2

[0020] Embodiment two: Weigh Ho2O3 and TiCl4 according to the chemical composition Ho2TiO7, dissolve them with 1:1 nitric acid to form a solution and remove excess acid, and add 15% ammonium sulfate and 0.4% PAA of the total molar amount of metal ions as a dispersant; Ammonium bicarbonate is made into solution with deionized water, ammonium bicarbonate is 6 times of the total molar weight of metal ions, and its volume is 2 times of the volume of metal ion mixed solution, and it is completely dissolved; At room temperature, slowly drop the configured solution into the ammonium bicarbonate at a rate of ≤10ml / min and stir. The precursor produced by reverse titration is flocculent and has a large specific surface area. Due to the addition of ammonium sulfate and PAA as a dispersant, this precursor can obtain particles with less agglomeration after calcination and has a higher specific surface area. Active, conducive to the preparation of transparent ceramics. After the titratio...

Embodiment 3

[0021] Embodiment Three : Weigh Gd2O3 and ZrOCl2.8H2O according to the chemical composition Gd2Zr2O7, dissolve them with 1:1 nitric acid to form a solution and remove excess acid, and add 20% of the total molar amount of metal ions at the same time. Ammonium sulfate and 0.3% of PAA are used as Dispersant; ammonium bicarbonate is made into a solution with deionized water, ammonium bicarbonate is 5 times the total molar weight of metal ions, and the volume is 1.5 times the volume of the metal ion mixed solution, and it is completely dissolved; At room temperature, slowly add the configured solution to ammonium bicarbonate dropwise at a rate of ≤5ml / min, and stir. The precursor produced by reverse titration is in the form of flocculent precipitation and has a large specific surface area. Due to the addition of ammonium sulfate as a dispersant, this precursor can obtain less agglomerated particles after calcination and has higher activity. It is beneficial to the preparation of ...

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

No PUM Login to View More

Abstract

The invention discloses a preparation method of pyrochlore-type A2B2O7 transparent ceramics, relating to A2B2O7-series nano powder preparation by a sol-gel process and belonging to the field of ceramic material preparation. The preparation method comprises the following steps: at room temperature, weighing RE2O3 and ZrOCl2.8H2O or TiCl4 according to the stoichiometric proportion, dissolving the rare earth oxide in nitric acid, adding the ZrOCl2.8H2O or TiCl4 to be dissolved, adding a mixed solution containing a dispersing agent (NH4)2SO4 and PAA (polyacrylic acid), slowly and dropwisely adding into an ammonium bicarbonate solution to obtain a precursor, and drying; adding a certain amount of sintering assistant ethyl orthosilicate or silicon dioxide sol into the precursor, carrying out ball milling, drying, screening and calcining to obtain nano powder; and carrying out compression molding, isostatic cool pressing, vacuum sintering, annealing and polishing treatment to finally obtain the transparent A2B2O7-series ceramics. By adopting the self-made high-activity nano powder to prepare the transparent A2B2O7-series ceramics at low temperature, the technique is simple and feasible.

Description

technical field [0001] The invention relates to the field of ceramic preparation, in particular to a method for preparing pyrochlore-type A2B2O7 transparent ceramics technical background [0002] Pyrochlore type A2B2O7 series (A: REE rare earth element; B: Ti or Zr), in the Ti system, the two compounds La2Ti2O7 and Nd2Ti2O7 belong to the monoclinic system, while other products (A=Sm-Lu) are calcined The green stone structure belongs to the cubic crystal system. In the Zr system, when A=La, Nd, Sm, Eu, Gd, it forms a pyrochlore structure, which belongs to the cubic crystal system, and when A=Tb-Lu, it forms a pyrochlore structure. The stone structure belongs to the cubic crystal system. Pyrochlore-type oxides are a series of compounds with similar structures, they have a unique crystal structure, and there are many functional substitution sites in the lattice, so they have many advantages in thermal, electrical, magnetic and catalytic aspects. Due to their unique propertie...

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): C04B35/50C04B35/622
Inventor 张扬吴少凡黄凌雄
Owner FUJIAN CASTECH CRYSTALS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com