Preparation method of tungsten carbide nanopowder

A technology of nano-tungsten carbide and powder, which is applied in the direction of nano-structure manufacturing, carbide, nano-technology, etc., can solve the problems that it is difficult to avoid ball milling medium pollution, unfavorable industrial production promotion, long reaction time, etc., and achieve small particle size, The effect of improving the purity of the powder and reducing the degree of agglomeration

Inactive Publication Date: 2011-09-21
SHANGHAI INST OF CERAMIC CHEM & TECH CHINESE ACAD OF SCI
View PDF3 Cites 23 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] At present, the conventional methods of tungsten carbide powder include oxide direct carbonization method, gas phase reaction method, mechanical alloy method, halide carbonization method, etc.: the gas phase reaction method needs to use the reduction and carbonization atmosphere as the reaction medium to obtain nano-tungsten carbide. The whole process The process is complicated and the reaction time is long; the high-energy ball milling method consumes a lot of energy and it is difficult to avoid the pollution of the ball milling medium during the ball milling process, which is not conducive to the promotion of industrial production

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 of tungsten carbide nanopowder
  • Preparation method of tungsten carbide nanopowder
  • Preparation method of tungsten carbide nanopowder

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] Weigh 10.0g ammonium metatungstate ((NH 4 ) 6 W 12 o 39 4H 2 (2, molecular weight 3010.35), and 17.7g of anhydrous citric acid, are dissolved in deionized water and are formulated into a clear solution. After fully stirring, the sol is processed in a water bath at 70° C., and then placed in an oven at a temperature of 100° C. The water in the sol is evaporated to form a gel, and then the temperature is raised to 200°C for 10 hours to obtain a tungsten-carbon precursor. The precursor was placed in a carbon tube furnace, and under vacuum conditions, the temperature was raised to 900°C at a rate of 5°C / min, and the nano-tungsten carbide powder was obtained after holding the temperature for 0.5 hours. figure 1 It is a transmission electron microscope photo of the powder, as shown in the figure, the average grain size of the powder is about 30nm, and the dispersion is good. The residual carbon content was measured to be 0.39 wt%.

Embodiment 2

[0027] Weigh 10.0g ammonium metatungstate (NH 4 ) 6 W 12 o 39 4H 2 O and 17.7g of anhydrous citric acid, the tungsten-carbon precursor was prepared according to the method in Example 1. The precursor was placed in a tube furnace, and the temperature was raised to 1000°C at a rate of 5°C / min under nitrogen atmosphere (nitrogen flow rate: 3L / h), and nano-tungsten carbide powder was obtained after holding for 2 hours. figure 2 It is the XRD pattern of tungsten carbide. It can be seen from the figure that the powder phase is almost pure WC phase, and the broadening of the diffraction peak is caused by the fine (nano-scale) tungsten carbide grains. The prepared powder has a residual C content of 0.32% and a particle size of 40nm.

Embodiment 3

[0029] Weigh 10.0g ammonium metatungstate (NH 4 ) 6 W 12 o 39 4H 2 O and 12.5g of anhydrous acetic acid were dissolved in deionized water to prepare a clear solution. After fully stirring, the sol was processed in a water bath at 70°C, and then placed in an oven at 100°C to obtain a tungsten carbide precursor. The precursor was placed in a carbon tube furnace, and the temperature was raised to 800°C at a rate of 10°C / min under vacuum conditions for 4 hours to obtain nano-tungsten carbide powder. The prepared powder has a residual C content of 0.43% and a particle size of 25nm.

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
particle sizeaaaaaaaaaa
Login to view more

Abstract

The invention provides a preparation method of tungsten carbide nanopowder. The preparation method comprises the following steps of: preparing a tungsten-carbon precursor by using soluble tungsten salt and organic acid as raw materials through a sol-gel method, and then carrying out heat treatment on the tungsten-carbon precursor to obtain the tungsten carbide nanopowder. The preparation method provided by the invention is simple and practical, avoids the multistep control mode of the traditional preparation methods, saves energy, and is suitable for industrial production; and the tungsten carbide nanopowder prepared by the invention has the advantages of uniform and small particle size (smaller than 50 nm), low aggregation degree, low impurity content and low residual carbon content (lower than 0.5wt%).

Description

technical field [0001] The invention relates to a method for preparing nanometer tungsten carbide powder, which belongs to the field of nanometer powder preparation. Background technique [0002] In recent years, the rapid development of IT industry, electronic technology and computer industry has put forward new requirements for tungsten carbide-based cemented carbide materials, that is, higher strength and hardness, while traditional cemented carbide has a large grain size (> 1μm), As a result, its strength and hardness are relatively low, and it has become increasingly difficult to meet the needs of contemporary technological development. Studies have shown that when the average grain size of WC in ultrafine cemented carbide is less than 0.5 μm, the strength, hardness, wear resistance and toughness of the material are greatly improved compared with traditional cemented carbide, and there is There is a tendency for further improvement due to size reduction. The emerge...

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): C01B31/34B82B3/00C01B32/949
Inventor 阚艳梅孙世宽张国军王佩玲
Owner SHANGHAI INST OF CERAMIC CHEM & TECH CHINESE ACAD OF SCI
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