Ultralow Thermal Conductivity of Highly Dense ZrW₂O₈ Ceramics with Negative Thermal Expansion

ZrW 2 O 8 is known as a negative coefficient of thermal expansion (CTE) material. In contrast, the studies other properties than CTE , such conductivity and mechanical properties, are limited. Herein, highly dense bulk sample (%T.D. > 95%) from very fine powder (D50 0.3 μm) with crystalline size 31 nm using spark plasma sintering (SPS) technique synthesized. It revealed that exhibits lowest level among various oxides in wide temperature range 300 to 823 K. Furthermore, physical peculiar CTE, elastic constant, Grüneisen parameter reported. Owing its exceptional expected be used management areas.