全氟十四酸包覆纳米铝粉的制备及点火燃烧性能

Preparation of Aluminum Nanopowders Coated with Perfluorotetradecanoic Acid and Its Ignition and Combustion Characteristics

在氮气气氛下,采用全氟十四酸(FS)对纳米铝粉(nmAl)进行了表面包覆,采用扫描电镜(SEM)、X射线衍射(XRD)和傅里叶变换红外(FT-IR)光谱对其形貌和结构进行了表征。用激光点火装置和低压火药燃烧测试装置对表面处理前后纳米铝粉的点火燃烧性能进行了研究。结果表明,全氟十四酸包覆的纳米铝粉(nmAl/FS),其分散性提高,颗粒分布更均匀;全氟十四酸羧基中的两个氧原子与纳米铝粉表面的Al原子以桥接的方式相结合;与未处理的纳米铝粉相比,在激光热流密度较低时,nmAl/FS的点火延迟时间短;在激光点火燃烧过程中,nmAl/FS的燃烧反应较剧烈,火焰亮度高,在低压火药燃烧测试装置中燃烧时,其燃烧火焰更集中,火焰亮度更高,燃烧更充分。

Aluminum nanopowders(nmAl) coated with perfluorotetradecanoic acid(FS)were obtained under nitrogen atmosphere,and their surface morphologies and structures were characterized by scanning electron microscope(SEM),X-ray diffraction(XRD),and Fourier transform infrared(FT-IR) spectroscopy.The ignition and combustion characteristics of aluminum nanopowders before and after treatment were studied by using the ignition device and low-pressure propellant combustion test device.The results show that the dispersity of aluminum nanopowders coated with FS was improved,and the particle size distribution was more homogeneous.The two oxygen atoms in carboxyl group of FS were combined with the Al atoms of aluminum nanopowders surface by the ways of bridging.Compared with the untreated aluminum nanopowders,the ignition delay time of nmAl/FS is shorter at the low laser heat flux density.In the laser ignition combustion process,the combustion reaction of nmAl/FS is more intense and the flame brightness is higher.During combustion of nmAl/FS at the low-pressure propellant combustion test device,the burning flame is more concentrated,the flame brightness is higher,and the burning is more sufficiently.