HyCEML - Hybrid CFRP/ elastomer/ metal laminates containing elastomeric interfaces for deliberate dissipation

该项目的主要目标是确定和调查由碳纤维增强聚合物(CFRP)、弹性体和金属(HyCEML)制成的混杂层板在平静、平滑和智能方面的优势和劣势。与传统的纤维-金属层合板不同，弹性体形成了金属和CFRP之间的界面，并建立了HyCEML通常非常好的减振(平静)性能。除了减振，该弹性体还涵盖了一系列在混合动力系统中至关重要的进一步(智能)方面。它起到了粘合剂的作用，从而促进了不同材料的连接。它补偿热膨胀系数不匹配(CTE不匹配)造成的内部应力，并作为绝缘层来抵消触点腐蚀。此外，由于弹性体层中的能量吸收和优异的抗分层性能，它显着提高了混杂层板的冲击耐受性。可以保证系统的无抖动(平稳)运行。因此，需要进行全面的实验和数值研究，这需要新的方法或方法的调整。由于混杂层合板的阻尼特性是高度各向异性的，本项目的目标之一是对各向异性行为及其潜在的机理进行实验表征。除了各向异性外，研究层合板的静力特性也是为了分析层合板的减振特性。除了对CAME性能的表征外，进一步的目标是对SMART方面的分析，例如CTE失配的补偿和腐蚀行为。基于实验结果，需要开发合适的有限元(FE)建模技术来数值描述层合板的阻尼行为。第一个建模目标是建立和验证详细的多层有限元模型，用于研究不同铺层和加载组成对减振性能的影响。为了验证和确认的目的，需要分析闭合形式的解(例如，对于简支板)和实验测试。此外，需要研究特定的层压板配置，以故意增加层压板的减振能力。由于多层壳单元的计算效率高于详细的多层有限元模型，因此需要一种合适的壳理论来在结构层面上模拟杂交层合板。根据多层建模的最新技术和即将获得的实验结果，拟议项目的一个基本目标是开发多层壳配方。该项目的另一个目的是调查不同几何方面对结构所产生的减振行为的影响。为此，将对具有不同几何复杂性的不同通用部件进行建模。

The main objective of the project is to identify and to investigate the advantages and disadvantages of hybrid laminates made of carbon fiber reinforced polymers (CFRP), elastomers and metals (HyCEML) in terms of ist calm, smooth and smart behavior. In contrary to conventional fiber-metal laminates, the elastomer forms the interface between metal and CFRP and establishes the generally very good damping (calm) behavior of HyCEML. Beyond damping, the elastomer covers a series of further (smart) aspects that are crucial in hybrid systems. It acts as adhesive and thus facilitates the joining of the dissimilar materials. It compensates internal stresses caused by a mismatch of the coefficients of thermal expansion (CTE mismatch) and acts as an insulating layer that counteracts contact corrosion. Furthermore it improves the impact tolerance of the hybrid laminate significantly due to energy absorption in the elastomer layer in combination with superior delamination resistance. A jerk-free (smooth) operation of the system can be assured. Therefore, comprehensive experimental and numerical investigations are needed, which require new methods or method adjustments. Since the damping characteristics of the hybrid laminate are highly anisotropic, one of the objectives of this project is the experimental characterization of the anisotropic behavior as well as their underlying mechanisms. In addition to anisotropy, investigating the calm properties aims for the analysis of the laminates damping characteristics. In addition to the characterization of the calm properties, a further objective represents the analysis of smart aspects such as the compensation of the CTE mismatch and the corrosion behavior. Based on the experimental results, suitable finite element (FE) modeling techniques need to be developed to describe the laminate damping behavior numerically. The first modelling objective is to build up and validate detailed multi-layer FE models to be used to investigate the effect of varying layup and loading constitutions on the damping behavior. For verification and validation purposes, analytical closed-form solutions (e.g. for simply supported plates) and experimental tests are needed. Furthermore, specific laminate configurations need to be investigated to deliberately increase the damping capability of the laminate. Since multi-layer shell elements are computationally more efficient than detailed multi-layer FE models, a suitable shell theory is needed to model the hybrid laminates on structural level. Based on the state of the art in multi-layer modelling and based on the experimental results to be obtained, an essential objective of the proposed project is the development of a multi-layer shell formulation. A further aim of the project is to investigate the influence of different geometric aspects onto the resulting damping behavior of the structure. To do this, different generic parts with varying geometrical complexity will be modelled.