کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
169603 | 458022 | 2010 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Heat of combustion of tantalum–tungsten oxide thermite composites Heat of combustion of tantalum–tungsten oxide thermite composites](/preview/png/169603.png)
The heat of combustion of two distinctly synthesized stoichiometric tantalum–tungsten oxide energetic composites was investigated by bomb calorimetry. One composite was synthesized using a sol–gel (SG) derived method in which micrometric-scale tantalum is immobilized in a tungsten oxide three-dimensional nanostructured network structure. The second energetic composite was made from the mixing of micrometric-scale tantalum and commercially available (CA) nanometric tungsten oxide powders. The energetic composites were consolidated using the spark plasma sintering (SPS) technique under a 300 MPa pressure and at temperatures of 25, 400, and 500 °C. For samples consolidated at 25 °C, the density of the CA composite is 61.65 ± 1.07% in comparison to 56.41 ± 1.19% for the SG derived composite. In contrast, the resulting densities of the SG composite are higher than the CA composite for samples consolidated at 400 and 500 °C. The theoretical maximum density for the SG composite consolidated to 400 and 500 °C are 81.30 ± 0.58% and 84.42 ± 0.62%, respectively. The theoretical maximum density of the CA composite consolidated to 400 and 500 °C are 74.54 ± 0.80% and 77.90 ± 0.79%, respectively. X-ray diffraction analyses showed an increase of pre-reaction of the constituents with an increase in the consolidation temperature. The increase in pre-reaction results in lower stored energy content for samples consolidated to 400 and 500 °C in comparison to samples consolidated at 25 °C.
Journal: Combustion and Flame - Volume 157, Issue 12, December 2010, Pages 2326–2332