Cold spray and mechanical bonding technology for the production of aerospace hybrid composites

飞机的主要结构不断被重新设计，以在不影响结构完整性和安全性的情况下减轻重量。顺应这一趋势，行业领先者采用了更大比例的碳纤维增强复合材料(CFRC)，以提高飞机蒙皮的强度重量比和抗机械应力能力。然而，在特定位置出现了磨损/侵蚀问题，导致迅速退化。目前，解决这一问题的方法是在关键区域通过昂贵且劳动密集型的方法在CFRC皮肤上成形和粘接钛板。可以预见，添加制造工艺可以提供比当前解决方案更好的替代方案。冷喷涂是一种适用于热敏衬底材料的低温添加剂制造工艺，可以沉积不同厚度的薄层材料。该项目建议使用Nucap的GRIP金属专利挂钩技术，在喷涂之前在CFRC上创建粘结层。这两种技术的结合旨在以经济高效的方式通过机械结合在CFRC上实现可靠和可重复的冷喷涂涂层。该项目使用GRIP金属钢板和铝板，而不是钛，以最大限度地减少成本，同时允许验证概念。将不同挂钩密度和大小的夹具金属板整合在未固化的碳纤维预浸料堆上，将制造出CFRC板。将对所得层压板的质量进行检测。根据用钢获得的初步结果，将在组件上喷涂钢涂层和铝涂层，以评估变厚度涂层的生产能力。拟议技术的成功开发和实施有可能大幅节省成本和缩短制造时间。

Aircraft primary structures are constantly being redesigned for reducing weight without encumbering structural integrity and safety. Following this trend, industry leaders incorporate a greater proportion of carbon fibre reinforced composites (CFRCs) that improve the aircraft skin's strength-to-weight ratio and resistance to mechanical stress. However, issues regarding wear/erosion at specific locations arise, leading to swift degradation. This is currently solved through costly and labour intensive methods of shaping and gluing titanium sheets on CFRC skins in critical areas. It is envisioned that additive manufacturing processes can offer better alternatives to the current solution. Cold spray is a low temperature additive manufacturing process suitable for heat sensitive substrate materials, that enables depositing thin layers of material in variable thickness. This project proposes to use Nucap's GRIP Metal patented hook technology to create a bond coat on CFRCs prior to spraying. The combination of both technologies aims at enabling reliable and reproducible cold spray coatings on CFRCs through mechanical bonding, in a cost effective way. The project uses GRIP Metal steel and aluminium sheets instead of titanium to minimize costs while allowing validation of the proof of concept. CFRC plates integrating GRIP Metal sheets with different hook densities and sizes will be manufactured by laminating on uncured carbon fibre prepreg stacks. The quality of the resulting laminates will be probed. Steel coatings and aluminium coatings, depending on initial results obtained with steel, will be sprayed on the assemblies to assess the productibility of variable thickness coatings. The successful development and implementation of the proposed technology has the potential to result in major cost savings and reduced manufacturing time.