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

High-density ceramic material as well as preparation method and application thereof

A ceramic material and density technology, which is applied in the field of high-density ceramic materials and its preparation, can solve the problems of low density of products, obstacles to the application and development of thermal protection of aerospace vehicles, and high sintering temperature

Active Publication Date: 2021-07-30
BEIJING INSTITUTE OF TECHNOLOGYGY
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the LaMgAl 11 o 19 Strong sintering resistance and high sintering temperature, it is difficult to achieve sintering densification under conventional molding and sintering processes
The existence of pores between grains makes it prone to brittle fracture during the working process, resulting in poor thermal shock resistance, and it is difficult to withstand large mechanical and thermal shocks
Although new sintering techniques such as hot pressing sintering and spark plasma sintering can be used to prepare high-density LaMgAl 11 o 19 Ceramics, but limited by the mold, these methods can only prepare samples with simple shapes, which are difficult to meet the complex and diverse requirements for sample shapes in practical applications
Although conventional pressureless sintering can prepare LaMgAl with corresponding shapes according to different requirements, 11 o 19 Sample, but the product density is not high (only 70% to 80%)
In view of the above factors, LaMgAl 11 o 19 Applications and developments in the thermal protection of aerospace vehicles and industrial furnaces are severely hampered

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
  • High-density ceramic material as well as preparation method and application thereof
  • High-density ceramic material as well as preparation method and application thereof
  • High-density ceramic material as well as preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0030] The present invention provides a preparation method for the high-density ceramic material described in the above technical solution, comprising the following steps:

[0031] Mixing lanthanum source, magnesium source, transition metal oxide, iron source, cobalt source, nickel source and aluminum source, carrying out stage-by-stage pressure-holding molding to obtain a green body; the lanthanum source, magnesium source, transition metal oxide, iron The molar ratio of lanthanum element, magnesium element, transition metal element, iron element, cobalt element, nickel element and aluminum element in source, cobalt source, nickel source and aluminum source is 1:(0.4-x):x:0.2:0.2: 0.2:11, 0<x≤0.2; the transition metal oxide includes copper oxide or zinc oxide;

[0032] Sintering the green body without pressure to obtain a high-emissivity high-entropy ceramic material;

[0033] The step-by-step pressure-holding molding process includes: the first stage: the molding pressure is 2...

Embodiment 1

[0050] La 2 o 3 Powder (average particle size 0.5 μm, purity ≥ 99.9%), FeO powder (average particle size 0.5 μm, purity ≥ 99.9%), CoO powder (average particle size 0.5 μm, purity ≥ 99.9%), NiO powder (average particle size 0.5μm, purity ≥ 99.9%), ZnO powder (average particle size 0.5μm, purity ≥ 99.9%), Al 2 o 3 Powder (average particle size 0.5 μm, purity ≥ 99.9%) and MgO powder (average particle size 0.5 μm, purity ≥ 99.9%) according to La (Mg 0.2 Zn 0.2 Fe 0.2 co 0.2 Ni 0.2 ) Al 11 o 19 The stoichiometric ratio is batched, where La 2 o 3 , FeO powder, CoO powder, NiO powder, ZnO powder, Al 2 o 3 The molar ratio of the powder and the MgO powder is respectively 1:0.4:0.4:0.4:0.4:11:0.4, and the obtained mixture is mixed with absolute ethanol to carry out wet ball milling, the ball milling speed is 280rpm, and the ball milling time is 18h, dark brown mixed powder was obtained;

[0051] Put the dark brown mixed powder into a stainless steel mould, first place the ...

Embodiment 2

[0054] La 2 o 3 Powder (average particle size 0.5 μm, purity ≥ 99.9%), FeO powder (average particle size 0.5 μm, purity ≥ 99.9%), CoO powder (average particle size 0.5 μm, purity ≥ 99.9%), NiO powder (average particle size 0.5μm, purity ≥ 99.9%), CuO powder (average particle size 0.5μm, purity ≥ 99.9%), Al 2 o 3 Powder (average particle size 0.5 μm, purity ≥ 99.9%) and MgO powder (average particle size 0.5 μm, purity ≥ 99.9%) according to La (Mg 0.2 Cu 0.2 Fe 0.2 co 0.2 Ni 0.2 ) Al 11 o 19 The stoichiometric ratio is batched, where La 2 o 3 , FeO powder, CoO powder, NiO powder, CuO powder, Al 2 o 3 The molar ratios of the powder and the MgO powder are respectively 1:0.4:0.4:0.4:0.4:11:0.4, the resulting mixture is mixed with absolute ethanol, and wet ball milled, the ball milling speed is 250rpm, and the ball milling time is 24h, Obtain dark brown mixed powder;

[0055] Place the dark brown mixed powder in the forward direction under the pressure of 3.2MPa and ho...

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 provides a high-density ceramic material as well as a preparation method and application thereof, and belongs to the technical field of ceramic materials. The chemical composition of the high-density ceramic material provided by the invention is La(Mg0.4-xTMxFe0.2Co0.2Ni0.2)Al11O19, and 0 < x < = 0.2. According to the preparation method of the high-density ceramic material, forming is conducted in a staged positive and negative pressure maintaining mode, the density of a green body can be improved, and then the density of a ceramic sample is improved; according to the invention, by adopting a forward and reverse two-way sequential pressurization mode, the non-uniformity of the density of the green body along the vertical direction can be eliminated, so that the density of the green body is further improved; and the ceramic material is pure in phase, the density is higher than 95%, the surface is free of micro cracks, the interior is free of micro holes, and the ceramic material can be widely used as a thermal protection material for aerospace crafts and a lining material for industrial kilns.

Description

technical field [0001] The invention relates to the technical field of ceramic materials, in particular to a high-density ceramic material and its preparation method and application. Background technique [0002] LaMgAl 11 o 19 Because of its high melting point, low density, low thermal conductivity and large thermal expansion coefficient, ceramics have become promising thermal protection materials for aerospace vehicles and lining materials for industrial kilns. According to the current application requirements, the materials promoted in the above fields need to have a long thermal cycle life and be able to withstand large thermal shocks. However, due to the LaMgAl 11 o 19 Strong sintering resistance and high sintering temperature, it is difficult to achieve sintering densification under conventional molding and sintering processes. The existence of pores between grains makes it prone to brittle fracture during the working process, resulting in poor thermal shock resis...

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): C04B35/50C04B35/44C04B35/622
CPCC04B35/50C04B35/44C04B35/622C04B2235/3227C04B2235/3206C04B2235/3272C04B2235/3275C04B2235/3279C04B2235/3217C04B2235/6562C04B2235/6567C04B2235/77
Inventor 刘玲马壮柳彦博朱皓麟
Owner BEIJING INSTITUTE OF TECHNOLOGYGY
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