Effects of Texture on the Thermal Conductivity of the LaPO4 Monazite

Abstract

LaPO4 monazite, as an excellent structural ceramic, is expected to have thermal conductivity anisotropy because of its asymmetric crystal structure (monoclinic). For this motivation, the LaPO4 samples with different degrees of texture are fabricated via varying the powder synthesis processes and using hot‐pressing sintering and spark plasma sintering technique. The effect of the texture on the thermal conductivity of the LaPO4 samples is subsequently explored in this study. The results reveal that the thermal conductivities of the LaPO4 samples decrease firstly with the increasing degree of preferred orientation of the (200) planes along the direction perpendicular to the pressing direction, and approach a particular value, which is possibly the conductivity of the LaPO4 single crystal along the direction perpendicular to the (200) planes (a‐axis direction), when the orientation achieves a certain degree. The longitudinal or transverse speeds of all the textured LaPO4 samples are also measured and used to clarify the thermal conductivity anisotropy.