Thermal conductivity of Y6WO12 and Yb6WO12 ceramics

► The high-density pellets of Y6WO12 and Yb6WO12 ceramics were prepared. ► The thermal conductivity (κ) of the ceramics was examined. ► It was revealed that the κ of Yb6WO12 was lower than that of Y6WO12. ► The heavy molecular mass and low Debye temperature of Yb6WO12 led to the low κ.