MACANTA:Multifunctional hierarchical advanced composite aerostructures utilising the combined properties of different carbon nanotube (CNT) assemblies

碳纤维复合材料客机的出现，如波音787和空客A350，主要是由于需要减轻结构重量。更高的运营效率也有助于减少对环境的影响，每节省1公斤燃料相当于减少3.15公斤二氧化碳排放。事实上，欧盟已经制定了雄心勃勃的飞机减排目标，到2050年，商业空中交通水平将继续每15年翻一番。碳纤维复合材料的高比强度和刚度以及耐腐蚀和抗疲劳性能使其非常适合轻型航空结构。在层压形式下，这些优越的性能被材料相对较低的穿透厚度强度和断裂韧性所调和，这使得复合材料结构容易受到冲击损伤。碳纤维复合材料的导电性也很低，因此需要额外的措施来确保足够的雷击保护。该行业已经采用了一个精细的金属网纳入空气动力学表面的使用。这种方法给结构增加了不必要的重量，也增加了制造和维护的复杂性。复合材料还具有导热系数低的特点，这影响了防冰系统的设计。近年来，许多研究小组已经探索了分散在树脂中或在层状界面之间引入的纳米颗粒的独特性质，以解决这些限制。特别是碳纳米管（CNTs）的使用，由于其非凡的结构和传输特性而引起了广泛的关注。迄今为止的结果变化很大，远远达不到预期。这部分是由于缺乏跨学科的合作，需要化学家、物理学家、材料科学家和研究工程师投入的基本问题没有得到充分的调查。MACANTA提出的研究旨在通过汇集一个具有高度互补专业知识的团队来纠正这一问题，以增加对不同碳纳米管组件的物理和化学特性影响的基本理解，从而开发多功能复合材料，减轻已知的缺点，并提供额外的功能。MACANTA的一个独特方面是强调理解和利用不同形式的碳纳米管组件，以最好地服务于特定功能，并集成在一个单一的结构中。该团队具有生产高质量碳纳米管的独特能力，以高度对齐的“森林”形式生产。这些可以以这种形式利用，并策略性地放置在层之间，以增加贯穿厚度的断裂韧性。除了简单地分散在基质中，它们也可以被“剪切”成排列整齐的纸，拉成非常薄的网或纺成纱线，在那里它们各自的电导率和导热性将被研究。这些碳纳米管组件将被评估以改善雷击保护和提供防冰能力。碳纳米管网的压阻性能也将用于粘接复合材料接头的原位结构健康监测。在MACANTA上提出的研究的成功完成将最终制造出一套演示多功能复合面板。它们将代表着最先进技术的重大进步，并为感兴趣的利益相关者提供竞争优势。它还将为昆士兰大学资助的三名博士后研究员和两名相关博士生的技能发展提供理想的培训平台。

The advent of carbon-fibre composite passenger aircraft, such as the Boeing 787 and the Airbus A350, has been primarily driven by the need to reduce structural weight. Higher operating efficiencies per revenue passenger kilometre also contribute to a reduction in environmental impact where 1 kg of fuel saved equates to a reduction of 3.15 kg of CO2 emissions. Indeed the European Union has set ambitious aircraft emission reduction targets by 2050 as the level of commercial air traffic is set to continue doubling every fifteen years. The high specific strength and stiffness, and corrosion and fatigue resistance of carbon-fibre composite materials, make them highly suitable for lightweight aerostructures. In laminated form, these superior properties are tempered by the material's relatively low through-thickness strength and fracture toughness which makes composite structures susceptible to impact damage. Carbon-fibre composites also have low electrical conductivity which necessitates the need for additional measures to ensure adequate lightning strike protection. The industry has adopted the use of a fine metallic mesh incorporated into the aerodynamic surfaces. This approach adds unnecessary weight to the structure as well as increasing manufacture and maintenance complexity. Composite materials also have low thermal conductivity which impacts on the design of anti-icing systems. In recent years, a number of research groups have explored the unique properties of nanoparticles dispersed in resin or introduced between lamina interfaces, to address these limitations. The use of carbon nanotubes (CNTs) especially, generated much excitement due their phenomenal structural and transport properties. The results to date have been highly variable and have fallen well short of expectations. This is partly due to a lack of interdisciplinary collaboration where fundamental questions, requiring input from chemists, physicists, material scientists and research engineers, were not adequately investigated. The proposed research in MACANTA aims to rectify this by bringing together a team with highly complementary expertise to increase the fundamental understanding of the influence of physical and chemical characteristics of different CNT assemblies in pursuit of developing multifunctional composites which mitigate the known shortcomings as well as providing additional functionality. A unique aspect of MACANTA is the emphasis on understanding and exploiting the different forms of CNT assemblies to best serve specific functions and integrated within a single structure. The team has the unique capability of producing very high quality CNTs, produced as highly-aligned 'forests'. These may be harnessed in this form and strategically placed between plies to increase through-thickness fracture toughness. Beyond simply dispersing within the matrix, they may also be 'sheared' to produce aligned buckypaper, drawn into very thin webs or spun into yarns, where their respective electrical and thermal conductivity will be investigated. These CNT assemblies will be assessed for improving lightning strike protection and providing anti-icing capability. The piezoresistive property of CNT webs will also be explored for in-situ structural health monitoring of adhesively bonded composite joints. The successful completion of the research proposed in MACANTA will culminate in the manufacture of a set of demonstrator multifunctional composite panels. They will represent a significant advancement in the state-of-the-art and provide a competitive advantage to interested stakeholders. It will also provide an ideal training platform for the development of skills of three postdoctoral researchers and two associated PhD students funded by QUB.