SBIR Phase I: Stabilization of Nanostructured Reactive Multilayers

小型企业创新研究(SBIR)第一阶段将开发一种新型的纳米工程多层膜，用于材料的反应连接，使人能够控制相应反应箔的稳定性和点火能量。在这个项目中将探索两种一般的方法。第一种方法是基于蒸汽沉积的周期性四层结构，在这种结构中，在具有高混合热的元素(Al和Ni)之间交替的两个纳米级层被由相对惰性的材料(铜)组成的较薄的阻挡层分开，该阻挡层与另外两个相互作用较弱。然后可以通过改变惰性(铜)阻挡层的纳米级厚度(0.5 nm到5.0 nm)来实现对箔的稳定性、点火要求和反应性能的控制。第二种方法是基于复合材料结构的发展，它将纳米级反应箔(50-150微米厚)与微米级的铜焊和焊料层结合在一起。在这种方法中，人们利用铜焊层和焊料层的热质量来提高反应箔的稳定性。在该项目中，该团队将(1)证明这种新型纳米工程多层膜的可行性，(2)表征其稳定性和点火要求，以及(3)开发和验证预测计算模型，以补充实验观察并扩大其范围。在商业上，这些新型纳米结构材料的成功开发将导致反应连接技术的显著改进。潜在客户和供应商的支持函显示出对开发稳定的反应性多层膜及其在连接应用中的使用的兴趣。

This Small Business Innovation Research (SBIR) Phase I will develop a new class of nano-engineered multilayers for reactive joining of materials that enables one to control the stability and ignition energy of the corresponding reactive foils. Two general approaches will be explored in this project. The first approach is based on vapor depositing a periodic quad-layer structure, in which two nanoscale layers, alternating between elements with high heats of mixing (Al and Ni), are separated by thinner, barrier layers comprised of a relatively inert material (Cu) that interacts weakly with the other two. Control over foil stability, ignition requirements and reaction properties can then be achieved by varying the nanoscale thickness (0.5nm to 5.0nm) of the inert (Cu) barrier layers. The second approach is based on the development of composite structures, which combine nanolayered reactive foils (50-150 micron thick) with micron scale braze and solder layers. In this approach, one takes advantage of the thermal mass of the braze and solder layers in order to enhance the stability of the reactive foil. In the project, the team will (1) demonstrate the feasibility of this new class of nano-engineered multilayers, (2) characterize their stability and ignition requirements, and (3) develop and validate predictive computational models that complement experimental observations and amplify their scope. Commercially, successful development of these novel nanostructed materials will lead to significant improvement in reactive joining technology. Letters of support from potential customers and suppliers demonstrate interest in the development of stable reactive multilayer foils and their use in joining applications.