Effect of preoxidation on microcracks in graphite foams

The formation mechanisms of microcracks in graphite foams were investigated by varying the preoxidation temperature of the precursor mesophase pitch. Results indicated that after the mesophase pitch was preoxidized, its quinolineinsoluble component became the dominant fraction, which leads to a decrease in heat stress gradient and as a result, a decrease in the amount, length and width of microcracks.