Method for preparing nanometer vanadium/chromium carbide composite powder by reduction with microwave method

A technology of composite powder and nano-chromium oxide, which is applied in the direction of nanotechnology, can solve the problems that cannot satisfy the application of vanadium carbide (chromium) powder, the particle size of the reaction product is coarse, and the content of free carbon is high, so as to reduce the reaction activation energy and particle size distribution. The effect of narrow range and lower reaction temperature

Inactive Publication Date: 2012-09-19
HENAN UNIVERSITY OF TECHNOLOGY
View PDF2 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method has higher reaction temperature (>1200°C), longer reaction time (>2h), and higher production cost
In addition, the particle size of the reaction product is relatively coarse, generally between 2 and 5 μm, and the free carbon content in the powder is high, which cannot meet the application of vanadium carbide (chromium) powder in modern industry

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

[0020] Take 7.35 g of nano-vanadium trioxide, 7.00 g of nano-chromium dioxide and 5.60 g of nano-carbon black according to the weight ratio, put them in a ball mill, use acetone as the ball milling medium, and mix thoroughly to obtain a mixture. Then the mixture was placed in a drying oven, dried at 200° C. for 1 hour, and the dried mixture was pressed into a block. Finally, the block is placed in a microwave sintering furnace, and under the protection of argon or hydrogen atmosphere, carbonization reduction is carried out at 1000 ° C for 5 minutes to obtain nano vanadium carbide / chromium carbide with an average particle size of <100nm and uniform particle size distribution. Composite powder. Compared with the traditional preparation method, the synthesis condition reduces the reaction temperature by 200-300°C and shortens the reaction time by 2-4 hours. And the product has the characteristics of small size and uniform dispersion.

Embodiment 2

[0022] Take 5.85 g of nano-vanadium pentoxide, 7.10 g of nano-chromium trioxide and 5.80 g of nano-activated carbon according to the weight ratio, put them in a ball mill, use absolute ethanol as the ball-milling medium, and mix thoroughly to prepare a mixture. Then the mixture was placed in a drying oven, dried at 100° C. for 3 hours, and the dried mixture was pressed into a block. Finally, the block is placed in a microwave sintering furnace, and carbonization reduction is carried out at 700°C for 30 minutes under vacuum conditions to obtain nano vanadium carbide / chromium composite powder with an average particle size of <100nm and uniform particle size distribution. Compared with the traditional preparation method, the synthesis condition reduces the reaction temperature by 500-600°C and shortens the reaction time by 2-4 hours. And the product has the characteristics of small size and uniform dispersion.

Embodiment 3

[0024] Take 6.20 g of nano-vanadium tetroxide, 5.40 g of nano-chromium trioxide and 5.40 g of nano-carbon black according to the weight ratio, put them in a ball mill, use absolute ethanol as the ball milling medium, and mix thoroughly to obtain a mixture. Then the mixture was placed in a drying oven, dried at 150° C. for 2 hours, and the dried mixture was pressed into a block. Finally, the block is placed in a microwave sintering furnace, and carbonization reduction is carried out at 900°C for 10 minutes under vacuum conditions to obtain nano-vanadium carbide / chromium composite powders with an average particle size of <100nm and uniform particle size distribution. Compared with the traditional preparation method, the synthesis condition reduces the reaction temperature by 300-400°C and shortens the reaction time by 2-4 hours. And the product has the characteristics of small size and uniform dispersion.

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 diameteraaaaaaaaaa
Login to view more

Abstract

A method for preparing nanometer vanadium/chromium carbide composite powder by reduction with a microwave method is characterized by comprising the following steps: a, taking 5.60-7.35 g of nanometer vanadium oxide, 5.40-7.10 g of nanometer chromium oxide and 5.40-6.20 g of carbonaceous reducing agent in proportion by weight, placing the materials into a ball mill, and fully mixing the materials by taking absolute ethyl alcohol or acetone as a ball-milling medium, so as to obtain a mixed material; b, placing the mixture obtained in the step a into a drying box, drying the mixture at the temperature of 100-200 DEG C for 1-3 hours, and then compressing the dried mixture into blocks for standby; and c, placing the blocks obtained in the step b into a microwave sintering furnace, performing carbonization reduction on the blocks at the temperature of 700-1000 DEG C for 5-30 minutes under the protection condition of vacuum, argon or hydrogen environment, so as to obtain the nanometer vanadium/chromium carbide composite powder with the average grain diameter of 100 nm and uniform grain fineness distribution.

Description

technical field [0001] The invention relates to a preparation method for reducing and synthesizing nano vanadium carbide / chromium composite powder by a microwave method, and belongs to the field of nano ceramic powder preparation. Background technique [0002] Transition metal carbide Vanadium (chromium) carbide has a high melting point, hardness and high temperature strength, as well as good electrical and thermal conductivity. It has a wide range of applications in metallurgy, electronics, catalysts and high-temperature coating materials. Among them, vanadium carbide (chromium) plays an important role as a grain inhibitor in the fields of cemented carbide and cermets. What is needed in industrial applications is vanadium carbide (chromium) powder with fine particle size and single phase composition. For example, when preparing ultra-fine cemented carbide, the particle size of WC powder should be less than 200nm, and high-pressure and low-temperature HIP sintering technolo...

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): C04B35/56C04B35/626B82Y40/00
Inventor 赵志伟郑红娟宋伟强刘国勤涂文斌张书军纪小会
Owner HENAN UNIVERSITY OF TECHNOLOGY
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