Introduction to High-purity graphite:
High-purity graphite refers to graphite with a carbon content greater than 99.99%. High-purity graphite flakes have characteristics such as complete crystal structure, thin and good toughness, excellent physical and chemical properties, good thermal conductivity, heat resistance, self-lubrication, conductivity, thermal shock resistance, and corrosion resistance. High-purity graphite has high strength, density, purity, chemical stability, high temperature resistance, uniform and dense structure, high conductivity, good wear resistance, and easy processing. It is widely used in metallurgy, chemical industry, aerospace, electronics, machinery, nuclear power, and other industrial fields. Especially large size, high-quality high-purity graphite, as a substitute material, has broad application prospects in high-tech fields.
Applications of High-purity graphite in industry:
High-purity graphite has been widely used in industry. It is widely used in the metallurgical industry as high-grade refractory materials and coatings, military explosive stabilizers, light industry, electric pencil brushes, industrial battery electrodes, and fertilizer industry additives and catalysts. High-purity graphite can be processed into various parts such as graphite grids in vacuum-packed food; graphite crucibles, graphite containers, heaters, and insulation covers in vacuum furnaces, single crystal furnaces, and electric furnaces; precious metal selenium alloy melting containers, molds; graphite molds for pressing hard alloys; graphite used in electrical discharge machining; wear-resistant and heat-resistant shafts; and various high-temperature heating elements. It can be processed according to samples and drawings provided by customers.
The production technology of high-purity graphite is generally the same as that of ordinary graphite, but it has the following characteristics: low ash raw materials must be selected, and the ash content of petroleum coke used as raw material shall not exceed 0.15%; high-purity graphite can be used for extrusion molding or molding. Fine-structured high-purity graphite is mostly used for compressive molding to process various shaped components, and can also be processed by isostatic pressing process. The key process to increase the purity of high-purity graphite is graphitization, and the graphitization temperature should be higher than the production temperature of ordinary graphite electrodes. Halogen gases are introduced to reduce the impurity content to around 150-200ppm during or after the graphitization process. During processing, the surface of high-purity graphite may become contaminated due to different working environments and processing techniques. Purification work can be carried out again to remove surface contamination. Some high-purity graphite products need to be coated with a layer of pyrolytic graphite to improve their oxidation resistance.