Fabrication and optical properties of Sm₂Zr₂O ₇-NiCr₂O₄

Sm₂Zr₂O₇ is one of the promising candidate materials for the next generation thermal barrier coatings because of its excellent thermal properties. But at high temperature the thermal conductivity of rare-earth zirconate increases because of radiation conduction. NiCr ₂O₄, which can absorb the infrared photons intensely, was introduced to reduce the radiation conduction of rare-earth zirconate. NiCr ₂O₄ powder was prepared by coprecipitation. The bulks of Sm₂Zr₂O₇-NiCr₂O₄ with different content of NiCr₂O₄ were prepared by using non-pressure sintering. The phase and microstructure of the samples were characterized by XRD and SEM. The optical absorption was also investigated. The absorptivity of the composite, which was generally higher than that of pure Sm₂Zr₂O₇ prepared by coprecipitation and non-pressure sintering, was enhanced with the content of NiCr₂O ₄ increasing. The enhancement of absorptivity will reduce the radiation conduction of rare-earth zirconate potentially.