Abstract The use of Al-based nano-energetic materials has been limited in part due to difficulties in fabrication of high-density composites. In this paper, free-standing energetic composites with loading of up to 90 wt% Al-CuO were fabricated by 3D printing. A polymer hybrid of 3 wt% hydroxy propyl methyl cellulose (HPMC), 3.5 wt% nitrocellulose (NC) and 3.5 wt% polystyrene (PS), enables fabrication of mechanically strong and highly reactive composites. The energy flux can be readily tuned through the combustion speed and flame temperature by changing equivalence ratio. The highest energy flux was found to occur under fuel rich conditions (equivalence ratio = 2.4) which also corresponds to the maximum combustion speed (25 cm/s) despite the fact that the flame temperatures was lower. The Young's modulus of free-standing burn sticks was found to be as high as ~1 GPa, which is comparable to pure polypropylene. PS polymer flakes created during the high shear direct write process is believed to be critical to the enhanced mechanical properties we observed. The burning behavior using other oxidizers corresponds closely with that observed with mixed powders but with the added strength offered in a printed structure. This study offers an attractive route for safe, reliable and scalable additive manufacturing of Al-based nano-energetic materials at high energy densities.

中文翻译：

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3D 打印 90 wt% 负载增强纳米铝热剂的燃烧

摘要 由于难以制造高密度复合材料，铝基纳米高能材料的使用受到限制。在本文中，通过 3D 打印制造了负载高达 90 wt% Al-CuO 的自支撑高能复合材料。3 wt% 羟丙基甲基纤维素 (HPMC)、3.5 wt% 硝化纤维素 (NC) 和 3.5 wt% 聚苯乙烯 (PS) 的聚合物混合物能够制造机械强度高且反应性高的复合材料。通过改变当量比，可以很容易地通过燃烧速度和火焰温度来调整能量通量。发现最高能量通量出现在富燃料条件下（当量比 = 2.4），这也对应于最大燃烧速度 (25 cm/s)，尽管火焰温度较低。年轻人' 发现独立燃烧棒的 s 模量高达 ~1 GPa，与纯聚丙烯相当。在高剪切直写过程中产生的 PS 聚合物薄片被认为对我们观察到的增强的机械性能至关重要。使用其他氧化剂的燃烧行为与使用混合粉末观察到的燃烧行为密切相关，但与印刷结构中提供的增加的强度一致。这项研究为安全、可靠和可扩展的高能量密度铝基纳米高能材料的增材制造提供了一条有吸引力的途径。使用其他氧化剂的燃烧行为与使用混合粉末观察到的燃烧行为密切相关，但与印刷结构中提供的增加的强度一致。这项研究为安全、可靠和可扩展的高能量密度铝基纳米高能材料的增材制造提供了一条有吸引力的途径。使用其他氧化剂的燃烧行为与使用混合粉末观察到的燃烧行为密切相关，但与印刷结构中提供的增加的强度一致。这项研究为安全、可靠和可扩展的高能量密度铝基纳米高能材料的增材制造提供了一条有吸引力的途径。