Artificial graphite blocks have excellent electrical, thermal, and chemical propertiesand are used in various applications. The impregnation process is an important step inthe artificial graphite block manufacturing process for achieving high density and optimizingvarious performances. However, during the re-carbonization process after the impregnationprocess, the impregnated pitch is melted via temperature increase for recarbonization,and its low molecular weight components are volatilized. This induces elutionof the impregnated pitch that filled the pores of the graphite block, resulting in adecrease in the impregnation rate and an increase in density. Re-impregnation and re-carbonizationprocesses, which are expensive and time-consuming, are required to be performedseveral times to achieve the desired density. Therefore, this study aims to addressthis issue by applying the pressurized heat treatment during the impregnation process.
The rates of density increase and impregnation rates are not significantly increased whencompared to those of the impregnated graphite block without pressurized-heat treatment.
However, it was found that about 10-20 bar of the pressure could be generated during thethe pressurized-heat treatment, resulting in the increased impregnation rate of the lowerpressure impregnation, which was similar to the higher pressure impregnation.