SBIR Phase I: Repair, Weld, and Build Metallic Parts with Fill Impact Welding

小型企业创新研究(SBIR)第一阶段项目的更广泛的商业影响旨在开发一种焊接技术，该技术将改善金属部件和特征的维修、连接和附加制造。最初的应用包括在飞机生产和服务过程中增加材料以修复钻头和误钻的孔，这两个都代表着巨大的财务机会。由于当前可用的修复方法对基础材料性能的不利影响，通常是由于极端温度，因此目前不允许在生产环境中对结构材料进行修复。飞机结构制造商有强烈的动机将飞机结构的重量降至最低，这往往是以报废整个面板的巨大财务和环境代价为代价的。维护、维修和大修通常需要用新部件完全更换损坏的部件，因为对关键部件的不当维修可能会造成灾难性的损害。由于航空航天工业的高价值、小批量的性质，更换部件的成本很高，而且交货期很长。该项目将开发一种有效的修复方法来修复金属部件，同时与材料和部件几何形状无关。回收由钛、镍和铝等材料制成的以前无法修复的部件对环境有很大的积极影响。此外，通过广泛实现固态连接，这项技术将颠覆全球价值200亿美元的焊接行业。由美国牵头的基础技术平台将在科学、技术和工程领域创造新的就业机会，同时支撑国内制造业供应链。支撑该项目的创新涉及使用爆炸焊接进行顺序、战术和可控的金属沉积。爆炸焊接使用硬币大小的金属元素，发射速度在300-1000米/S范围内，不含爆炸物。虽然众所周知，爆炸焊接可以将大型板材焊接在一起，但这种方法不适用于自动化或传统的工业环境。冲击焊接将发展为一种填充焊接技术，很像传统焊接中的填充金属，并将使用锻造的薄板作为原料。在这里，将使用电气化金属箔作为填充元件的驱动器，研究重点将集中在这些元件是否可以重复发射以开发更大的键合区域和可重复定位。在飞行过程中控制元件形状和方向并产生完全焊接的界面的能力是该技术最高风险的方面。将进行机械测试、扫描电子显微镜和在线过程监测，如光子多普勒测速仪。这项工作将开发一种新的工艺-结构-性能循环，目标是生产出比竞争技术(如冷喷涂)生产的部件更好的部件，以总能耗、成本和机械性能衡量。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The broader/commercial impact of this Small Business Innovation Research (SBIR) Phase I project seeks to develop a welding technology that will improve the repair, joining, and additive manufacturing of metallic parts and features. First applications include material additions to repair gouges and mis-drilled holes during aircraft production and service, both of which represent significant financial opportunities. Repairs to the structural material are not currently permissible in a production environment due to adverse effects of currently available repair methods on base material properties, usually due to extreme temperatures. Aerostructure manufacturers have a strong incentive to minimize the weight of the aircraft structure, often at the significant financial and environmental expense of scrapping a whole panel. Maintenance, repair and overhaul often entails total replacement of damaged components with new ones as improper repairs of critical components can cause catastrophic harm. Replacement of parts is expensive and has long lead times due to high-value, low-volume nature of the aerospace industry. This project will develop an effective restoration method to repair of metallic components, while being agnostic to the material and part geometry. Reclamation of previously unrepairable parts made from materials such as titanium, nickel, and aluminum has a large positive environmental impact. Additionally, by broadly enabling solid-state joining, this technology will disrupt the welding industry, globally valued at $20 billion. The foundational technology platform, led in the US, will produce new jobs in science, technology and engineering fields while bolstering domestic manufacturing supply chains.The innovation underpinning this project involves the sequential, tactical, and controlled deposition of metals using explosive welding. Explosive welding uses coin-sized metallic elements launched to speeds in the range of 300-1000m/s without explosives. While it is known that explosive welding can weld large plates together, the method is not suited to automation or conventional industrial settings. Impact welding will be developed as a fill-welding technique, much like a filler metal in conventional welding, and will use wrought sheet metal as feedstock. Here, electrically vaporized metallic foils will be used as the driver for the fill elements and the research will focus on whether those elements can be launched reproducibly to develop large bond areas and reproducible positioning. The ability to control element shape and orientation during flight and produce an interface that is fully welded are the most high-risk aspects of the technology. Mechanical testing, scanning electron microscopy, and inline process monitoring such as photonic Doppler velocimetry will be performed. This effort will develop a new process-structure-property loop, with the goal of producing parts that are better than those made with a competing technology such as cold spray as measured by total energy consumption, cost, and mechanical properties.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.