Synthesis of Zr(2)WP(2)O(12)/ZrO(2) Composites with Adjustable Thermal Expansion

Zr(2)WP(2)O(12)/ZrO(2) composites were fabricated by solid state reaction with the goal of tailoring the thermal expansion coefficient. XRD, SEM and TMA were used to investigate the composition, microstructure, and thermal expansion behavior of Zr(2)WP(2)O(12)/ZrO(2) composites with different mass ratio. Relative densities of all the resulting Zr(2)WP(2)O(12)/ZrO(2) samples were also tested by Archimedes' methods. The obtained Zr(2)WP(2)O(12)/ZrO(2) composites were comprised of orthorhombic Zr(2)WP(2)O(12) and monoclinic ZrO(2). As the increase of the Zr(2)WP(2)O(12), the relative densities of Zr(2)WP(2)O(12)/ZrO(2) ceramic composites increased gradually. The coefficient of thermal expansion of the Zr(2)WP(2)O(12)/ZrO(2) composites can be tailored from 4.1 × 10(−6) K(−1) to −3.3 × 10(−6) K(−1) by changing the content of Zr(2)WP(2)O(12). The 2:1 Zr(2)WP(2)O(12)/ZrO(2) specimen shows close to zero thermal expansion from 25 to 700°C with an average linear thermal expansion coefficient of −0.09 × 10(−6) K(−1). These adjustable and near zero expansion ceramic composites will have great potential application in many fields.