Ca[4(1+x)/5]Mg[(1+x)/5]Zr4Si2xP(6-2x)O24 phosphate negative-expansion ceramic material and preparation method thereof

A ceramic material and phosphate technology, applied in the field of low thermal expansion ceramics, can solve the problems of pure NZP compounds that are difficult to sinter and affect thermal shock resistance

Inactive Publication Date: 2010-12-29
CHINA UNIV OF GEOSCIENCES (BEIJING)
View PDF0 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, pure NZP compounds are difficult to sinter. For example, powder compacts made by solid-state reaction methods need to be kept at high temperature for at least 48 hours; at the same time, the expansion coefficient of ZN

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

[0014] Analytical pure sample calcium carbonate (CaCO 3 ), basic magnesium carbonate (4MgCO 3 ·Mg(OH) 2 ·5H 2 O), zirconia (ZrO 2 ), silicon dioxide (SiO 2 ) and phosphorus pentoxide (P 2 o 5 ) as raw material, according to the stoichiometric formula Ca 4(1+x) / 5 Mg (1+x) / 5 Zr 4 Si 2x P (6-2x) o 24 , Calculate the quality of various raw materials according to x=0.3, and then carry out batching separately. Then, the powder was mixed with agate balls and alcohol, ball milled for 6 hours, dried in an oven at 100°C for 12 hours, solid-phase synthesized in a box furnace, kept at 400°C for 2 hours, and kept at 1150°C for 4 hours to obtain a powder. Mix the obtained powder with alumina balls and alcohol, ball mill for 4 hours, and dry in an oven at 100°C for 8 hours. After the powder is dry-pressed at a pressure of 20 MPa, it is subjected to cold isostatic pressing at 200 MPa, and the holding time is 3 minutes. Finally, put it into a box furnace, heat-preserve and sinter ...

Embodiment 2

[0017] Analytical pure sample calcium carbonate (CaCO 3 ), basic magnesium carbonate (4MgCO 3 ·Mg(OH) 2 ·5H 2 O), zirconia (ZrO 2 ), silicon dioxide (SiO 2 ) and phosphorus pentoxide (P 2 o 5 ) as raw material, according to the stoichiometric formula Ca 4(1+x) / 5 Mg (1+x) / 5 Zr 4 Si 2x P (6-2x) o 24 , Calculate the quality of various raw materials according to x=0.2, and then carry out batching separately. Then, the powder was mixed with agate balls and alcohol, ball milled for 6 hours, dried in an oven at 100°C for 12 hours, solid-phase synthesized in a box furnace, kept at 400°C for 2 hours, and kept at 1150°C for 4 hours to obtain a powder. Mix the obtained powder with alumina balls and alcohol, ball mill for 4 hours, and dry in an oven at 100°C for 8 hours. After the powder is dry-pressed at a pressure of 20 MPa, it is subjected to cold isostatic pressing at 200 MPa, and the holding time is 3 minutes. Finally, put it into a box furnace, heat-preserve and sinter ...

Embodiment 3

[0019] Analytical pure sample calcium carbonate (CaCO 3 ), basic magnesium carbonate (4MgCO 3 ·Mg(OH) 2 ·5H 2 O), zirconia (ZrO 2 ), silicon dioxide (SiO 2 ) and phosphorus pentoxide (P 2 o 5 ) as raw material, according to the stoichiometric formula Ca 4(1+x) / 5 Mg (1+x) / 5 Zr 4 Si 2x P (6-2x) o 24 , Calculate the quality of various raw materials according to x=0.4, and then carry out batching separately. Then, the powder was mixed with agate balls and alcohol, ball milled for 6 hours, dried in an oven at 100°C for 12 hours, solid-phase synthesized in a box furnace, kept at 400°C for 2 hours, and kept at 1150°C for 4 hours to obtain a powder. Mix the obtained powder with alumina balls and alcohol, ball mill for 4 hours, and dry in an oven at 100°C for 8 hours. After the powder is dry-pressed at a pressure of 20 MPa, it is subjected to cold isostatic pressing at 200 MPa, and the holding time is 3 minutes. Finally, put it into a box furnace, heat-preserve and sinter ...

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
Average linear expansion coefficientaaaaaaaaaa
Bending strengthaaaaaaaaaa
Average linear expansion coefficientaaaaaaaaaa
Login to view more

Abstract

The invention relates to a Ca[4(1+x)/5]Mg[(1+x)/5]Zr4Si2xP(6-2x)O24 (CMZP for short) phosphate negative-expansion ceramic material and a preparation method thereof, belonging to the technical field of low-heat-expansion ceramic material. The preparation method comprises the following steps: using sodium zirconate-phsophate MIMIIZr4(PO4)6(NZP) ceramic system as a base body; doping a certain amount of alkaline earth metal elements Ca and Mg at MI position and MII position; replacing P with less Si; and sintering the mixed material at the temperature of 1200-1500 DEG C for 0.1-10h to obtain the CMZP ceramic material with the composition Ca[4(1+x)/5]Mg[(1+x)/5]Zr4Si2xP(6-2x)O24 (X is neither smaller than 0 nor greater than 1). The obtained material has high dense degree and low porosity, the average heat expansion coefficient is negative, and the material belongs to negative-expansion ceramic material. The material can be used for adjusting the expansion coefficient of the composite materials and producing zero-expansion or negative-expansion material, and also can be applied to the fields such as heat isolation, low-temperature sealing, gradient material, nuclear waste curing and corrosion inhibitors.

Description

technical field [0001] The present invention relates to a Ca 4(1+x) / 5 Mg (1+x) / 5 Zr 4 Si 2x P (6-2x) o 24 A phosphate negative expansion ceramic material and a preparation method thereof belong to the field of low thermal expansion ceramics. Background technique [0002] Ceramic materials are susceptible to external temperature changes, which generate thermal stress in the material, resulting in failure of the ceramic material. Negative thermal expansion ceramic materials refer to a class of ceramic materials whose average linear expansion coefficient or volume expansion coefficient is negative within a certain temperature range. Therefore, it has significant advantages in thermal shock resistance and is widely used, and has always been a research hotspot in the field of materials science. [0003] Sodium zirconium phosphate M I m II Zr 4 (PO 4 ) 6 (NZP) family phosphate is a kind of thermal expansion material with stable structure skeleton, when M I , M II Whe...

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
IPC IPC(8): C04B35/447C04B35/48C04B35/622
Inventor 闵鑫熊翠娥易帅王凡房明浩黄朝晖刘艳改
Owner CHINA UNIV OF GEOSCIENCES (BEIJING)
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products