Comparison of engineered nanocoatings on the combustion of aluminum and copper oxide nanothermites
Comparison of engineered nanocoatings on the combustion of aluminum and copper oxide nanothermites
复制标题
DOI：
10.1016/j.surfcoat.2012.07.094
复制
发表时间：
2013-01
影响因子：
5.4
通讯作者：
Eric S. Collins;M. Pantoya;Ashwin Vijayasai;T. Dallas
中科院分区：
文献类型：
--
作者：
Eric S. Collins;M. Pantoya;Ashwin Vijayasai;T. Dallas
开发了用于纳米含能复合材料浸没燃烧的防水纳米涂层。这些涂层可用于海洋发电、水下军械、推进、金属切割和火炬技术。通过气相技术将纳米涂层沉积在铝热剂颗粒上。研究的两种沉积技术是化学气相沉积（CVD）和原子层沉积（ALD）。铝热剂颗粒上总共涂覆了六种纳米涂层。探索了生产涂层的各种工艺参数。使用傅里叶变换红外光谱 (FTIR)、扫描电子显微镜 (SEM)、原子力显微镜 (AFM) 和接触角测角仪对纳米涂层进行表征。纳米涂层铝热剂颗粒的浸没燃烧测试是根据浸没时间进行的。将颗粒浸没在去离子水中3、5和10天。对铝热反应释放的能量进行了分析，并与其他类型的纳米涂层颗粒进行了比较。将氟碳自组装单层 (FSAM) 涂层的初步结果与由 Al2O3 组成的 ALD 涂层进行了比较。结果表明，随着浸没时间的增加，所有测试涂层的气泡能量与燃烧总能量的比率（Kc=Kbubble/Kcombustion）均下降。 FSAM包覆颗粒和Al2O3 ALD包覆颗粒的初始气泡能量分别为133.3和142.2（KJ/Kg）。浸泡10天后，气泡能量分别降至10.4和15.6（KJ/Kg）。 FSAM 涂层的 Kc 值降低了 12.8 倍，而采用 Al2O3 涂层的 ALD 则降低了 9.1 倍。疏水涂层对于能量产生至关重要，因为没有它，颗粒就不会点燃，从而导致 100% 的能量损失。
Water-repellent nano-coatings for submerged combustion of nano-energetic composite materials were developed. These coatings may have applications for oceanic power generation, underwater ordnance, propulsion, metal cutting, and torch technologies. Nano-coatings were deposited on thermite pellets by a vapor-phase technique. Two types of deposition techniques studied were chemical vapor deposition (CVD) and atomic layer deposition (ALD). A total of six types of nano-coatings were applied on the thermite pellets. Various process parameters to produce the coatings were explored. Characterization of the nano-coatings was carried out using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and contact angle goniometry. Submerged combustion tests of the nano-coated thermite pellets were performed as a function of submerged time. The pellets were submerged in de-ionized water for 3, 5, and 10days. The energy released by the thermite reaction was analyzed and compared to other types of nano-coated pellets. Initial results of a fluorocarbon self-assembled monolayer (FSAM) coating were compared with an ALD coating composed of Al2O3. Results show that with increasing submerged time, there was a decrease in the ratio of bubble energy to total energy of combustion (Kc=Kbubble/Kcombustion) for all coatings tested. The initial bubble energy of the pellets coated with FSAM and ALD with Al2O3was 133.3 and 142.2 (KJ/Kg), respectively. After submersion for 10days, the bubble energy reduced to 10.4 and 15.6 (KJ/Kg), respectively. The value of Kcfor the FSAM coating decreased by a factor of 12.8 whereas the ALD with Al2O3coating decreased by a factor of 9.1. The hydrophobic coating is critical for energy generation because without it, the pellets do not ignite, resulting in 100% loss of energy.