Preparation method and application of boride ceramic precursor

A technology of ceramic precursors and borides, applied in the field of ultra-high temperature ceramics, can solve the problems of low product purity, high preparation temperature, humidity sensitivity, etc., and achieve the effect of high purity, low preparation temperature and easy composition

Active Publication Date: 2014-10-08
NAT UNIV OF DEFENSE TECH
View PDF6 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In view of this, the present invention uses water-soluble zirconium (Zr) and hafnium (Hf) metal salts as the corresponding metal source, and the mixture of water-soluble hydroxycarboxylic acid and water-soluble polyhydric alcohol is the carbon source, and the polyhydric alcohol is also used as the follow-up gel simultaneously. The cross-linking a

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
  • Preparation method and application of boride ceramic precursor
  • Preparation method and application of boride ceramic precursor
  • Preparation method and application of boride ceramic precursor

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] a) ZrOCl with a molar ratio of 1:0:15:400 2 ·8H 2 O, malic acid, glycerol and solvent distilled water are added in the beaker, placed on a magnetic heating stirrer, stirred until each reactant is dissolved, after cooling, add boric acid with a Zr molar ratio of 8:1 into the beaker, and heat to Stir at 80°C for 20 minutes to dissolve the boric acid, and obtain ZrB after cooling 2 Ceramic precursors;

[0041] b) ZrB 2 The ceramic precursor was heated at 200°C for 5 hours to obtain a crosslinked precursor;

[0042] c) Put the crosslinked precursor into an alumina crucible, put it into a high-temperature pyrolysis furnace, raise the temperature to 1600°C at 7°C / min under an argon atmosphere, then vacuumize it, and keep it under vacuum for 0.5h to obtain ZrB 2 ceramics.

Embodiment 2

[0044] a) ZrO(NO 3 ) 2 ·xH 2 O. Add malic acid, glycerol and solvent distilled water into the beaker, place it on a magnetic heating stirrer, heat to about 40°C and stir until the reactants are completely dissolved. After cooling, add boric acid with a molar ratio of 2:1 to Zr In a beaker, heat to 60°C and stir for 80 minutes to dissolve the boric acid, and get ZrB after cooling 2 Ceramic precursors;

[0045] b) ZrB 2 The ceramic precursor was heated at 120°C for 20 hours to obtain a crosslinked precursor;

[0046] c) Put the cross-linked precursor into an alumina crucible, put it into a high-temperature cracking furnace, raise the temperature to 1200°C at 7°C / min under an argon atmosphere, and then vacuumize it, and keep it under vacuum for 4h to obtain ZrB 2 ceramics.

Embodiment 3

[0048] a) HfCl with a molar ratio of 1:1:8:800 4 , tartaric acid, ethylene glycol and solvent distilled water into the beaker, placed on a magnetic heating stirrer, heated to about 40 ℃ and stirred until the reactants are completely dissolved, after cooling, add boric acid with a molar ratio of 6:1 to Zr into the beaker , heated to 70°C and stirred for 40 minutes to dissolve boric acid, and HfB was obtained after cooling 2 Ceramic precursors;

[0049] b) HfB 2 The ceramic precursor was heated at 160°C for 8 hours to obtain a crosslinked precursor;

[0050] c) Put the cross-linked precursor into an alumina crucible, put it into a high-temperature cracking furnace, raise the temperature to 1500°C at 7°C / min under an argon atmosphere, and keep it warm for 3h to obtain HfB 2 ceramics.

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 sizeaaaaaaaaaa
Login to view more

Abstract

The invention provides a preparation method and application of a zirconium (Zr) and hafnium (Hf) boride superhigh-temperature ceramic liquid-phase precursor. According to the preparation method disclosed by the invention, the boride ceramic precursor is prepared by taking water-soluble inorganic salts of zirconium (Zr) and hafnium (Hf) as the sources of metal elements in corresponding ceramics, a mixture of water-soluble hydroxycarboxylic acid and water-soluble polyalcohol as a carbon source, diboron trioxide and boric acid as corresponding boron sources and distilled water as a solvent; corresponding boride ceramic powder is prepared through crosslinking splitting. The ceramic precursor provided by the invention has the advantages of low cost, low toxicity and environmental protection, simplicity in preparation, good stability in air, long-time placing and the like. The prepared boride ceramic powder has the characteristics of relatively high purity, good crystallinity, small particle size and the like. The preparation method of the boride precursor is expected to be applied to the synthesis and preparation of a superhigh-temperature ceramic precursor, preparation of a composite material through precursor transformation, preparation of superfine superhigh-temperature ceramic powder and the like.

Description

technical field [0001] The invention relates to the field of ultra-high-temperature ceramics, in particular to a preparation method of a boride ceramic precursor and its application in the preparation of high-temperature ceramic materials. Background technique [0002] With its high speed and fast response capability, hypersonic vehicles have gradually become the main development direction of aerospace and weapon systems, and will play an important role in future national security. However, the aerodynamic heating phenomenon of the nose cone and the leading edge of the wing is very prominent, and the development and application of new thermal protection materials are urgently needed. Ultrahigh temperature resistant ceramics and their composites are considered to be the most promising material systems for thermal protection systems of hypersonic vehicles. Ultra-high temperature ceramics refer to ceramic materials with a melting point higher than 3000°C, mainly including carb...

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): C04B35/58
Inventor 曹英斌严春雷刘荣军张长瑞王思青李斌
Owner NAT UNIV OF DEFENSE TECH
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap