Influence of bonding carbon on low carbon Al2O3-C refractory composites

The carbonized behavior of binders (carbores pitch, mesophase pitch, high temperature pitch and phenolic resins) was investigated. Meanwhile, the influence of binders, Ni-catalyst and heat treatment on structure and properties of low carbon Al2O3-C materials was researched. Mesophase pitch and high molecular weight resin provided higher carbon yield. The synergistic interaction of pitch and phenolic resin provided the higher carbon yield than that of single component. Ni-catalyst changed structure and morphology of bonded carbon promoting the transition of amorphous carbon to crystalline carbon increasing carbon yield and degree of graphitization. High molecular weight phenolic resins, mesophase or carbores pitch and Ni-catalyst worked together providing low carbon Al2O3-C samples of excellent strength performance in a wide temperature range and high resistance of thermal shock. Embedding coke in N2 could promote the generating of carbon fibers which obviously enhanced thermal shock resistance of low carbon (6% flake graphite) Al2O3-C materials after heat treatment.