共沉淀法制备负热膨胀性ZrW2O8粉体及其粒径控制初探

Negative thermal expansion (NTE) material ZrW2O8 powders were synthesized using co-precipitation route. The precursor of ZrW2O8 was studied by Thermogravimetric and differential scanning calorimetry (TG-DSC). The structure and morphology of the resulting powders were characterized by Powder X-ray diffraction (XRD) and Scanning electron microscopy (SEM), respectively. The results showed that the samples were single phase of α- ZrW2O8 with regular shape. High temperature X-ray diffraction measurement indicated that the thermal expansion coefficient of ZrW2O8 was - 10.35 ×10-6 K-1 in the temperature range from room temperature to 150 ℃, - 3.08 × 10-6 K-1 from 200 ℃ to 600 ℃ and the average value was - 5.38 ×10-6 K-1. At the same time, polyethylene glycol (PEG) was used as dispersant to primary control the size of ZrW2O8.