Preparation of ultrafine W-Ag composite powders by sol-gel method
ZHANG Fu-bin1, HU Yan-ling2, HU Ye-qi2, XU Long-shan2, HU Bai-xin3
1. School of Mechanical and Automotive Engineering, Xiamen University of Technology, Xiamen 361024, China 2. School of Materials Science and Engineering, Xiamen University of Technology, Xiamen 361024, China 3. School of Materials Science and Engineering, Hu’nan University, Changsha 410082, China
Abstract：W-20%Ag (mass percent) composite powders were prepared by sol-gel method with AgNO3 and (NH4)6H2W12O40·5H2O as raw materials and citric acid as a chelating reagent．The decomposition process of dry gel was checked by means of thermogravimetric analysis. The phase composition, particle size and morphology of the powders were studied by XRD and SEM. The results show that precursor powders undertake a series of decomposing and compound reactions during calcination and reduction. With the increasing of temperature, the phase composition, particle morphology, as well as particle size of the powder change apparently. The granularity of the W-20%Ag (mass percent) composite powders is about 200-400 nm．
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2015, Vol. 25 
