Oxide composite nuclear fuel pellet and preparation method thereof

A nuclear fuel and oxide technology, applied in the direction of reactor fuel elements, reactor fuel materials, nuclear engineering, etc., can solve the problems of poor thermal conductivity and low production efficiency, and achieve the goal of reducing sintering temperature, increasing density, and refining grains Effect

Inactive Publication Date: 2021-02-12
MATERIAL INST OF CHINA ACADEMY OF ENG PHYSICS
View PDF9 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problems of poor thermal conductivity and low production efficiency of the existing oxide composite nuclear fuel pellets, and to provide a high thermal conductivity oxide composite nuclear fuel by using flash firing technology to improve sintering efficiency and optimize the material structure Pellets and their preparation method

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
  • Oxide composite nuclear fuel pellet and preparation method thereof
  • Oxide composite nuclear fuel pellet and preparation method thereof
  • Oxide composite nuclear fuel pellet and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] to UO 2 Nano powder (powder particle size is about 100nm) and SiC whisker (whisker length is about 9 μm, diameter is about 1 μm) as raw materials, the mass fraction of silicon carbide whiskers is 5%, and the total amount of raw materials is 50g;

[0031] Put the raw material powder into a ball mill jar, add zirconia grinding balls and 20 mL of ethanol, and ball mill and mix the mixture for 20 h at a speed of 100 r / min.

[0032] After mixing, the slurry was heated and stirred at 90°C and dried; the dried mixed powder was put into a cemented carbide mold for compression molding, and pressed into an embryo body with a mass of about 2g with an axial pressure of 4MPa, and then Compaction is carried out by cold isostatic pressing at a pressure of 100-300Mpa and a holding time of 1-20min.

[0033] Put the green body after cold isostatic pressing into the sintering device of the flash firing system, and pass in nitrogen gas, connect the electrodes at both ends of the green bod...

Embodiment 2

[0036] to UO 2 Nano powder (powder particle size is about 1 μm) and carbon nanotube powder (powder particle size is about 100nm) as raw materials, the mass fraction of carbon nanotubes is 3%, and the total amount of raw materials is 50g;

[0037] Put the raw material powder into a ball mill jar, add zirconia grinding balls and 20 mL of ethanol, and ball mill and mix the mixture for 15 hours at a speed of 100 r / min.

[0038] After mixing, the slurry was heated and stirred at 90°C and dried; the dried mixed powder was put into a cemented carbide mold for compression molding, and pressed into a green body with a mass of about 2g under an axial pressure of 4MPa, and then Cold isostatic pressing is carried out at a pressure of 150Mpa and a holding time of 20min for compaction.

[0039]Put the green body after cold isostatic pressing into the sintering device of the flash firing system, connect the electrodes at both ends of the green body, start the power supply (apply a constant ...

Embodiment 3

[0042] With ThO 2 (powder particle diameter is about 200nm) and carbon nanotube powder (powder particle diameter is about 100nm) is raw material as raw material, and the mass fraction that carbon nanotube accounts for is 10%, and the total amount of raw material is 40g;

[0043] Put the raw material powder into a ball mill jar, add zirconium dioxide grinding balls, 15 mL of ethanol, and ball mill the mixture for 15 hours at a speed of 150 r / min.

[0044] After mixing, the slurry was heated and stirred at 90°C and dried; the dried mixed powder was molded, pressed into a green body with a mass of about 2g under an axial pressure of 4MPa, and then cold isostatic pressed on the pressure 200Mpa, holding time 10min for compaction.

[0045] Put the green body after cold isostatic pressing into the sintering device of the flash firing system, and pass in hydrogen gas, connect the electrodes at both ends of the green body, start the power supply (apply Constant electric field), the f...

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 diameteraaaaaaaaaa
lengthaaaaaaaaaa
Login to view more

Abstract

The invention provides a preparation method of an oxide composite nuclear fuel pellet, and belongs to the technical field of nuclear material preparation. The preparation method comprises the following steps: 1) preparing mixed powder: putting oxide nuclear fuel powder and filler powder into a ball-milling tank, adding zirconium dioxide grinding balls, mixing and carrying out ball milling; 2) compression molding: carrying out compression molding on the ball-milled mixed powder, and demolding to obtain an oxide composite nuclear fuel blank; 3) flash burning: electrifying the oxide composite nuclear fuel blank body, applying constant electric fields to two ends of the blank body, simultaneously raising the temperature, and carrying out flash burning when the flash burning temperature is met,wherein the current is a constant current of 0-700mA / mm < 2 >, the field intensity is 0-300V / cm, the flash burning temperature is 25-1000 DEG C, and the flash burning time is 0-600s; and after flashburning is completed, cooling and demolding and obtaining the oxide composite nuclear fuel pellet. According to the method, the constant direct-current electric field is applied to the two ends of theblank by utilizing a flash burning technology, so that the sintering temperature of uranium dioxide or thorium dioxide can be remarkably reduced, the sintering time is shortened and the density of the material is improved.

Description

technical field [0001] The invention belongs to the technical field of nuclear material preparation, in particular to an oxide composite nuclear fuel pellet and a preparation method thereof. Background technique [0002] Uranium dioxide (UO 2 ) is currently the most widely used nuclear fuel in commercial nuclear reactors. It has excellent thermal, chemical, and radiation stability, and has good compatibility with cladding materials. It is an ideal nuclear fuel. However, relying on the characteristics of phonon heat transfer leads to its low thermal conductivity under high temperature and irradiation conditions, which has become an important factor limiting the performance of nuclear reactors, and the low thermal conductivity of uranium dioxide fuel pellets is also a factor causing nuclear accidents one. Therefore, increasing UO 2 The thermal conductivity of fuel pellets is an effective means to improve the safety of nuclear power plants. Currently by applying the UO 2 C...

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): C04B35/80C04B35/50C04B35/622G21C3/62
CPCC04B35/50C04B35/622G21C3/623C04B2235/6567C04B2235/666C04B2235/6562C04B2235/6565Y02E30/30
Inventor 徐晨王力潇张鹏程白彬
Owner MATERIAL INST OF CHINA ACADEMY OF ENG PHYSICS
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