High Temperature Decomposition Behavior of CaZrO₃ Coating on Graphite for TiNi Alloy Melting

Abstract

In order to restrain the carbon pollution, the feasibility of CaZrO₃ coating was studied. The precursor powder was synthesized via solid-state reaction using metal calcium as a raw material. The protective coating on graphite was prepared by impregnation sintering method, and the effects of slurry viscosity, graphite density and coating thickness for coating were compared. The phase composition and microstructure of coatings were characterized, and the thermodynamic process was analyzed when the coating composition changed from CaZrO₃ to ZrC. The results show that vacuum sintering can result in the decomposition of CaZrO₃ and an intact ZrC coating with beautiful porous structure can be obtained.

Keywords

CaZrO₃ / ZrC / impregnation / coated graphite / decomposition

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