制备方法对Al/Fe_2O_3纳米铝热剂性能的影响

分别采用超声共混法、机械球磨法和溶胶-凝胶法制备出Al/Fe2O3纳米铝热剂。研究了3种制备方法对纳米铝热剂晶型、平均粒径、形貌、比表面积和热反应性能的影响。结果表明,超声共混法只能使两组分简单地混合在一起;机械球磨法通过机械作用力使两组分混合均匀,但部分Al颗粒破裂,平均粒径减小;溶胶-凝胶法制备的Fe2O3凝胶均匀包裹着Al颗粒,形成核壳结构的Al/Fe2O3纳米铝热剂,有效地保护了Al颗粒,同时纳米铝热剂具有高的比表面积,固—固反应放热量为896J/g。

Effects of Preparation Method on the Properties of Al/Fe2O3 Nano-thermites

Al/Fe2O3nano-thermites were prepared by using ultrasonic,mechanical milling and sol-gel methods,respectively.The influence of three kinds of preparation methods on the structures and properties of the final thermites,such as crystal structure,particle size,morphology,surface area and thermal performances,were studied.The results indicate that raw materials were simply mixed at nanoscale by ultrasonic method,part of the Al particles were breakdown by using milling mehtod,the average particle size of Al decrease and the formation of core-shell structure of Al/Fe2O3by sol-gel method effectively protected the Al,leading to a higher surface area and heat release of 896J.g-1.