Low-temperature sintering of ZrW2O8–SiO2 by spark plasma sintering

Amorphous ZrW 2 O 8 powder and amorphous SiO 2 powder were prepared by a sol–gel process as raw materials, and high-density ZrW 2 O 8 –SiO 2 were successfully prepared at a much lower temperature of 923 K for a much shorter holding time of 10 min by spark plasma sintering (SPS) method rather than by conventional melt-quenching method. The relative densities of 0.85ZrW 2 O 8 –0.15SiO 2 and 0.70ZrW 2 O 8 –0.30SiO 2 were 99.4% and 96.6%, respectively. The combined technique of a sol–gel process and SPS should enable us to prepare the varied types of high-density composites of ZrW 2 O 8 without severe thermal cracking caused by melt-quenching. The thermal expansion properties and dielectric properties of ZrW 2 O 8 –SiO 2 were also investigated.