Ultra-low thermal expansion behavior of spark plasma sintered Sn-doped ZrMo<inf>2</inf>O<inf>8</inf>

Sn-doped ZrMo2O8 exhibits a coefficient of thermal expansion that is tunable based on the amount of Sn present in the Zr lattice sites. The current study focuses on the facile sintering of this material using spark plasma sintering (SPS) process. Powder particles of the material were produced by co-precipitation, and the formation of the desired cubic phase was confirmed using X-ray diffraction. The powder particles were sintered using SPS at different temperatures to identify the optimum sintering conditions. The extremely high rate of heating during SPS process enables complete sintering while retarding the decomposition reactions. It was noticed that attaining dense phase pure samples is strongly dependent on the sintering conditions. The results from the dilatometry carried out on the sintered pellets resulted in ultra-low thermal expansion coefficients in the order of 10−7/°C for the samples sintered at 500°C. Comparisons with other commercially available low coefficient of thermal expansion materials highlight the advantage of the current work.