Preparation method of high-purity nuclear graphite

Abstract

The invention discloses a preparation method of high-purity nuclear graphite, and provides graphite, wherein the ash content of the graphite is less than about 300 ppm; the boron equivalent of the graphite is less than about 5.0 ppm; and the isotropous ratio of the graphite is about 0.85-1.5, which is calculated by dividing the CTE (Coefficient of Thermal Expansion) in the crosscutting texture direction by the CTE in the texture direction. The preparation method disclosed by the invention comprises the following steps of: grinding uncalcined needle coke into fine powder, mixing the fine coke powder with an adhesion agent, namely asphalt, then, grinding the mixture to form moulding powder, uniformly moulding the powder to form an expected shape of a graphite part, and roasting, densifying and graphitizing the blank product so as to obtain high-purity graphite having high isotropy. The high-purity nuclear graphite prepared by the invention is free from impurities and still has improved isotropy and controllable average density and bending strength; and thus, the high-purity nuclear graphite can be applied to a new generation of nuclear fission and ultra-high-temperature reactors.

Description

technical field [0001] The invention relates to the technical field of graphite, in particular to a method for preparing high-purity nuclear graphite. Background technique [0002] my country is a large country with natural graphite resources, and its reserves, output and export volume rank first in the world. However, due to insufficient investment in technology development, raw material production and processing of flake graphite are still the main products. Carbon-graphite materials are emerging materials with great prospects and are widely used in high-tech fields. [0003] At present, the flexible graphite industries in the United States, Japan, Germany, and France are in the leading position. Among them, only Japan can produce high-purity flexible graphite, and the world's largest flexible graphite output is more than 15,000-20,000 tons. my country's new flexible graphite industry is under construction and development. During the "Eighth Five-Year Plan" period, a bat...

AI Technical Summary

Problems solved by technology

my country's new flexible graphite industry is under construction and development. During the "Eighth Five-Year Plan" period, a batch of flexible graphite processing technology and equipment achievements have been made, but it is still in the trial production stage.