Synthesis and oxidation behavior of the materials based on carbon fibers and ultra-high temperature binary and high-entropy carbides

Abstract

The paper reports the results obtained in the experimental studies of the oxidation behavior of powders based on carbon fibers (graphite) and carbides of metals of groups IV and V of the periodic table, including high-entropy carbide (HEC) TiZrNbHfTaC5. The materials were synthesized by vacuum-free electric arc method using X-ray fibrous amorphous carbon and metal oxides as a starting material. X-ray diffractometry of the synthesis products identified graphite, titanium, zirconium, niobium, hafnium, and tantalum carbides, and HEC TiZrNbHfTaC5. Scanning electron microscopy of the synthesis products showed carbon fibers with the surface modified by the above-mentioned carbides. Differential thermal analysis was performed to determine the parameters of the oxidation process of these materials; the main difference between the synthesized materials is the oxidation rate, with the lowest one demonstrated by the high-entropy carbide containing material.