Preparation and heat insulating capacity of Sm₂Zr₂O₇-SiC composites based on photon thermal transport

A series of Sm₂Zr₂O₇-SiC composites doped with different volume fraction and particle size of SiC were prepared by hot pressing at 1300 ℃. The phase of the composites prepared is P-Sm₂Zr₂O₇ and C-SiC, and no other diffraction peaks exist, which indicates that Sm₂Zr₂O₇ has great chemical compatibility with SiC. The thermal conductivity and phonon thermal conductivity of the Sm₂Zr₂O₇-SiC composites are measured by the laser pulse method. The photon thermal conductivity of the composites is obtained by subtracting the phonon thermal conductivity from the total thermal conductivity. The results show that the photon thermal conductivity of Sm₂Zr₂O₇-SiC composites is lower than that of pure Sm₂Zr₂O₇. The photon thermal conductivity of Sm₂Zr₂O₇-SiC composites decreases first and then increases with the increase of SiC particle size. Sm₂Zr₂O₇-(5 vol%, 10 μm)SiC composite has the lowest photon thermal conductivity.