AEGIS (Advanced EnerGy-Absorption polymer for Impact-resistant Smart composites)

AEGIS（用于抗冲击智能复合材料的先进能量吸收聚合物）

• 批准号: EP/T000074/1
• 负责人: Fulvio Pinto
• 金额: $ 22.14万
• 依托单位: University of Bath
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FT000074%2F1
• 关键词: AEGIS; Advanced; EnerGy; Absorption; polymer

The development of a new generation of advanced fibrous composite materials plays a key role in the future evolution of the aerospace sector due to their very high weight-to-strength ratio that can lead to higher operating efficiencies per revenue passenger kilometre. However, while the fibre dominant properties guarantee excellent in-plane load-bearing characteristics, traditional composite materials exhibit weak resistance to out-of-plane loads, making them susceptible to delamination damage under impact loads that can happen during manufacturing or in service. Indeed, while for metallic media, which are homogeneous and can dissipate energy through yielding, a surface dent will only increase strain hardening locally, for composite materials it is associated with the separation of interior plies due to their intrinsic layered structure, and therefore it must be avoided since it can grow uncontrollably compromising the integrity of the entire structure and leading to severe local degradation of the mechanical properties and, in some cases, sudden critical failures. This weak impact resistance together with the complexity of the failure mechanisms typical of composite systems led in the past decade to the definition of the current design philosophy in aeronautical structures as a "no damage growth" approach, leading to overdesigned structures with high thickness and mainly quasi-isotropic layout based on the assumption of the presence of defects from the outset. Based on these premises, it appears clear the need of a comprehensive solution for the aerospace sector that matches the requirements of lightweight structures with the need for high impact resistance. AEGIS is aimed at the development of a novel hybrid composite material with exceptional energy absorption property which is based on the development of a new "smart" "pseudo non-Newtonian" polymer that can be used in traditional manufacturing processes of plate-like components and complex sandwich panels. The exceptional impact resistance of these new structures is caused by a dynamic stiffening effect given by the transient nature of a large number of crosslink bonds present in the new smart polymer, which forces the polymeric chains to dissipate a large quantity of energy in order to disentangle themselves when subjected to an external load. The development of this new polymeric layer will eliminate the issues associated with moisture absorption of traditional liquid media, allowing its efficient and rapid application on laminated structures as a "smart layer" that can be used as a superficial coating with a minimum effect on the final weight of the structure. Furthermore, due to the higher viscosity of the polymer, it will be possible to intercalate it within a scaffold material in order to develop a "smart core", guarantying ease of manufacturing and increasing the stiffness of the frequency-dependant polymer, leading to the development of novel hybrid sandwich structures. The hybrid composite materials developed in AEGIS will be able to actively respond to specific external stimuli via dynamically enabling the entanglement of the polymeric chains only when the solicitations are above a critical threshold. By combining the exceptional in-plane specific properties of composite materials with the outstanding out-of-plane resistance of the smart polymer, AEGIS will tackle the current limitations of composite components leading to a general increase of the reliability of composite structures that can change the current design approach reducing the safety parameters and optimising the geometries of current components.

新一代先进纤维复合材料的开发在航空航天领域的未来发展中发挥着关键作用，因为它们具有非常高的重量强度比，可以提高每收入乘客公里的运营效率。然而，虽然纤维的主要特性保证了优异的面内承载特性，但传统的复合材料对面外载荷的抵抗力较弱，使得它们在制造或使用过程中可能发生的冲击载荷下容易发生分层损坏。实际上，对于均匀的并且可以通过屈服来耗散能量的金属介质，表面凹陷将仅局部地增加应变硬化，而对于复合材料，由于其固有的层状结构，表面凹陷与内部层片的分离相关联，因为它会不受控制地生长，损害整个结构的完整性，在某些情况下，突然的严重故障。这种弱的抗冲击性以及复合材料系统典型的失效机制的复杂性导致在过去十年中将航空结构中的当前设计理念定义为“无损伤增长”方法，导致过度设计的结构具有高厚度并且主要是基于从一开始就存在缺陷的假设的准各向同性布局。基于这些前提，显然需要为航空航天领域提供一种全面的解决方案，以满足轻质结构的要求和高抗冲击性的要求。AEGIS旨在开发一种具有特殊能量吸收性能的新型混合复合材料，该材料基于一种新型“智能”“伪非牛顿”聚合物的开发，该聚合物可用于板状部件和复杂夹层板的传统制造工艺。这些新结构的特殊抗冲击性是由动态硬化效应引起的，该动态硬化效应由存在于新智能聚合物中的大量交联键的瞬时性质给出，其迫使聚合物链耗散大量能量，以便在受到外部载荷时使其自身解开。这种新的聚合物层的开发将消除与传统液体介质的吸湿相关的问题，允许其作为“智能层”有效和快速地应用于层压结构，可以用作表面涂层，对结构的最终重量影响最小。此外，由于聚合物的较高粘度，将有可能将其插入支架材料中以开发“智能芯”，从而简化制造并增加频率依赖性聚合物的刚度，从而导致新型混合夹层结构的开发。在AEGIS开发的混合复合材料将能够通过动态地使聚合物链的缠结，只有当招标高于临界阈值时，才能积极响应特定的外部刺激。通过将复合材料的特殊面内特性与智能聚合物的出色面外阻力相结合，AEGIS将解决复合材料组件的当前限制，从而普遍提高复合材料结构的可靠性，从而改变当前的设计方法，减少安全参数并优化当前组件的几何形状。

项目成果

A multifunctional ultra-thin acoustic membrane with self-healing properties for adaptive low-frequency noise control.

• DOI: 10.1038/s41598-022-22441-4
• 发表时间: 2022-10-22
• 期刊: Scientific reports
• 影响因子: 4.6

Investigation of a dynamic active/passive noise cancellation of polyborosiloxane thin membrane gel

• DOI: 10.1117/12.2660857
• 发表时间: 2023-04
• 作者: Konstantinos Myronidis;G. M. Malfense Fierro;M. Meo;F. Pinto

Impact-responsive layer based on encapsulated solid/liquid non-Newtonian polymers

• DOI: 10.1117/12.2660419
• 发表时间: 2023-04
• 作者: A. Hegazy;Konstantinos Myronidis;M. Meo;F. Pinto

ENHANCED ANTI-IMPACT PERFORMANCE OF COMPOSITE SANDWICH PANELS WITH MODIFIED POLYURETHANE FOAM CORES, EXPLOITING PHASE TRANSITION OCCURRENCE OF NON-NEWTONIAN POLYMER.

利用非牛顿聚合物的相变现象，增强具有改性聚氨酯泡沫芯的复合夹芯板的抗冲击性能。

• 发表时间: 2022
• 期刊: Composites Meet Sustainability
• 作者: Myronidisa K.

European Workshop on Structural Health Monitoring - EWSHM 2022 - Volume 1

欧洲结构健康监测研讨会 - EWSM 2022 - 第 1 卷

• DOI: 10.1007/978-3-031-07254-3_85
• 发表时间: 2023
• 作者: Myronidis K