Freeze drying preparation method for ultra-fine tungsten-doped yttrium oxide composite powder

A technology of composite powder and yttrium oxide, which is applied in the field of freeze-drying preparation of ultrafine yttrium oxide-doped tungsten composite powder, can solve the problems of serious grain agglomeration, particle size, precursor powder segregation, and grain growth, etc., to achieve Uniform distribution, low cost, small distribution and good effect

Active Publication Date: 2018-11-02
TIANJIN UNIV
View PDF7 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The serious segregation of the precursor powder will lead to the overall growth of the grains in the subsequent calcination and reduction process; the morphology of the precursor powder will also be inherited to W-Y 2 o 3 Composite powder, severe grain agglomeration and uneven particle size
The particle size of yttrium oxide-doped tungsten composite powder prepared by freeze-drying has never been reported to be less than 10nm

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
  • Freeze drying preparation method for ultra-fine tungsten-doped yttrium oxide composite powder
  • Freeze drying preparation method for ultra-fine tungsten-doped yttrium oxide composite powder
  • Freeze drying preparation method for ultra-fine tungsten-doped yttrium oxide composite powder

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037](1) Dissolve 2g of AMT and 0.1332g of yttrium nitrate hexahydrate in 100mL of deionized water, then dissolve 0.1g of PVP k-12 in it, and finally add to 200ml with deionized water (the concentration of AMT is 0.01g / mL, The mass of yttrium nitrate hexahydrate is 6.66% of the mass of ammonium metatungstate), and it is fully dissolved and dispersed by ultrasonic treatment (ultrasonic treatment power is 60W, ultrasonic time is 3h) to obtain a mixed solution.

[0038] (2) Then pour it into a watch glass and put it in the refrigerator, the pre-freezing temperature is -60°C, and pre-freeze for 8 hours.

[0039] (3) After the temperature of the lyophilizer reaches the freezing temperature of -60°C and stabilizes, put the pre-frozen watch glass into the lyophilizer, turn on the vacuum pump and maintain a vacuum of 1.0 Pa, and freeze-dry for 18 hours.

[0040] (4) Calcining the freeze-dried powder in air at 450° C. for 1.5 h to obtain a composite oxide powder.

[0041] (5) The com...

Embodiment 2

[0043] (1) Dissolve 2g of AMT and 0.1332g of yttrium nitrate hexahydrate in 4mL of deionized water, then dissolve 0.05g of PVP k-30 in it, and finally add to 8ml with deionized water (the concentration of AMT is 0.25g / mL, nitric acid The mass of yttrium hexahydrate is 6.66% of the mass of ammonium metatungstate), and it is fully dissolved and dispersed by ultrasonic treatment (ultrasonic treatment power is 300W, ultrasonic treatment time is 1h) to obtain a mixed solution.

[0044] (2) Then pour it into a watch glass and place it in the refrigerator at -60°C for 6 hours.

[0045] (3) After the temperature of the lyophilizer reaches the freezing temperature of -40°C and stabilizes, put the pre-frozen watch glass into the lyophilizer, turn on the vacuum pump and maintain a vacuum of 20 Pa, and freeze-dry for 48 hours.

[0046] (4) Calcining the freeze-dried powder in air at 500° C. for 0.5 h to obtain a composite oxide powder.

[0047] (5) The composite oxide powder is subjected...

Embodiment 3

[0049] (1) Dissolve 2g of AMT and 0.0533g of yttrium nitrate hexahydrate in 25mL of deionized water, then dissolve 0.3g of PVP k-60 in it, and finally add to 50ml with deionized water (the concentration of AMT is 0.04g / mL, nitric acid The mass of yttrium hexahydrate is 2.66% of the mass of ammonium metatungstate), and it is fully dissolved and dispersed by ultrasonic treatment (ultrasonic treatment power is 100W, ultrasonic time is 2h) to obtain a mixed solution.

[0050] (2) Then pour it into a watch glass and place it in the refrigerator at -30°C for 12 hours.

[0051] (3) After the temperature of the lyophilizer reaches the freezing temperature of -55°C and stabilizes, put the pre-frozen watch glass into the lyophilizer, turn on the vacuum pump and maintain a vacuum of 8 Pa, and freeze-dry for 12 hours.

[0052] (4) Calcining the freeze-dried powder in air at 400° C. for 1.8 h to obtain a composite oxide powder.

[0053] (5) The composite oxide powder is subjected to two-s...

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 freeze drying preparation method for ultra-fine tungsten-doped yttrium oxide composite powder. According to the freeze drying preparation method, a surface-active agent polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) or polyoxyethylene lauryl ether are added on the basis of freeze drying for in-situ preparing of about 10 nm of ultra-fine nanometer W-Y2O3 composite powder. The freeze drying preparation method comprises the steps that ammonium meta-tungstate, yttrium nitrate hexahydrate and a surface-active agent are dissolved into water and are fully dispersed anddissolved through ultrasonic treatment; then a mixture is placed in a refrigerator to be pre-frozen for a period of time; after being pre-frozen, the mixture is put into a freeze dryer to be subjected to freeze drying; a freeze-dried loose structure is ground and calcined in air so as to remove the surface-active agent, and thus WO3-Y2O3 composite powder is obtained; and finally, two-step reduction is conducted through hydrogen, and thus the ultra-fine tungsten-doped yttrium oxide composite powder is obtained. The powder, with the surface-active agent being added, prepared through the freezedrying method is small in particle aggregation, the average grain size reaches about 10 nm, granularity distribution of grains is extremely narrow, and second-phase Y2O3 is distributed quite evenly.

Description

technical field [0001] The invention provides a technology of a freeze-drying preparation method of ultrafine yttrium oxide-doped tungsten composite powder, which belongs to the technical field of powder preparation engineering. Background technique [0002] Tungsten alloy has high density and good comprehensive mechanical properties, so it is considered to be a very important penetrator material for military armor-piercing projectiles and armor-piercing projectiles. Meanwhile, tungsten-based materials are also considered to be the most promising plasmonic facing materials (PFMs). However, tungsten-based alloys still have many limitations, such as low-temperature brittleness, low recrystallization temperature, and insufficient density. Adding rare earth oxides to achieve dispersion strengthening, the performance of tungsten-based alloys has been greatly improved, among which Y 2 o 3 The strengthening effect of the addition is the most obvious. In addition, the effective ...

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): B22F9/22
CPCB22F9/22
Inventor 马宗青扈伟强董智柳楠刘永长王祖敏余黎明李冲刘晨曦
Owner TIANJIN UNIV
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