Oxidation Resistance of Nano-Reinforced PC-Refractories Modified with Phenol Formaldehyde Resin. Part 4. Thermodynamic Evaluation of Phase Formation Within Mg–O–C–Al, Mg–O–C–Ni and MgO–Al2O3–NiO–SiO2 Systems Using SiC + Al + Ni (NiO) Complex Antioxidant1

Resumo

Results are given for the synthesis and co-existence of phases formed from components of complex organic-inorganic antioxidant formed during modification of phenol-formaldehyde resin (PFR) and graphite with silica alkoxide and inorganic or organic nickel precursors. Thermodynamic analysis is given for the Mg–Al–C and Mg–O–Ni–C systems. It is shown that the periclase and carbon can coexist with aluminum and nickel, and also that oxidized antioxidants Al₂O₃ and NiO can interact respectively with the periclase and with the synthesized SiC formed during modification of PFR with silica. In considering the NiO–MgO–Al₂O₃–SiO₂ system it is established that during service noble spinel will be synthesized from the complex antioxidant components, facilitating an increase in PC-refractory durability in service.