Al/PVDF-Al/CuO/PVDF层间堆积多层膜的制备及其燃烧性能研究

The Preparation and Combustion Performance of Al/PVDF Laminated Films Sandwiched with Al/CuO/PVDF Thermite Layers

为了研究Al/CuO铝热剂的高能量释放速率对Al/PVDF薄膜燃烧性能的影响,采用静电喷雾沉积法将Al/CuO/5%PVDF或Al/CuO/10%PVDF铝热剂与Al/PVDF薄膜原位层间堆积得到多层复合薄膜,通过调控Al/CuO/PVDF铝热剂的组成结构和厚度来调控该薄膜的燃烧性能,获得了该多层薄膜的线性燃速、可视化火焰温度和归一化热密流随铝热剂组成和厚度的变化规律。结果表明,铝热剂的组成和厚度直接决定薄膜的燃速大小和燃烧传热方式,除了Al/PVDF-Al/CuO/5%PVDF 3层薄膜表现为对流燃烧,燃速(104±10)cm/s,火焰温度2700K,其他多层薄膜的燃速只有5.5~12.0cm/s、火焰温度只有1570~1700K,Al/PVDF层对Al/CuO/5%PVDF或Al/CuO/10%PVDF层的紧密约束将铝热剂燃烧的对流传热方式可能转化为热传导和热辐射传热。Al-PVDF反应和Al-CuO反应之间的相互作用削弱了Al/CuO/PVDF铝热剂的高能量密度和高能量释放速率优势。

In order to study the effect of the high energy release rate of Al/CuO thermite on the combustion performance of Al/PVDF films,herein,films with sandwich structure were prepared by in-situ laminated Al/CuO/5%PVDF or Al/CuO/10%PVDF thermite layers with Al/PVDF layers using the electrospray deposition method.The linear burning rate,visualized flame temperature and normalized heat flux of those laminated films with different composition and thickness of thermite layer were obtained.The results indicate that the composition and thickness of the thermite layer directly determine the burning rate and combustion heat transfer mode of laminated films.The burning rate of those laminated films are only 5.5—12.0cm/s,and the flame temperature is 1570—1700K,except for the 3 layers Al/PVDF-Al/CuO/5%PVDF laminated film exhibits convective combustion with burning rate of(104±10)cm/s and flame temperature of 2700K.It suggests that the tight restraint of Al/PVDF layer to Al/CuO/5%PVDF or Al/CuO/10%PVDF thermite layer may convert the convective heat transfer mode of thermite combustion to heat conduction and heat radiation.The interaction between the Al/PVDF reaction and the Al/CuO reaction weakens the advantages of high energy density and high energy release rate of the Al/CuO/PVDF thermite layer.