Simulation-supported research of novel textile-based adaptive fiber plastic composite structures with shape memory alloy elements for complex deformation patterns

高性能纤维材料，如玻璃纤维和碳纤维长丝，及其纺织加工成合适的增强半成品，是重型纤维增强聚合物复合材料（FRPC）的基础。通过将执行器和/或传感器功能集成到复合材料中，该材料组的功能范围可以显着扩展。特别是执行器材料，如形状记忆合金（SMA），在复合结构的主动功能化方面表现出特别高的潜力。该项目的目标是实现基于可重复和空间复杂变形行为的自适应复合材料的新型可变形状轻量化结构。在这里，具有热固性基体体系的玻璃纤维纺织增强复合材料将通过定位和纺织集成纱线或线状SMA致动器到纺织增强结构中来实现功能化。其中一个重点是SMA致动器在复合材料中的特定和自动化/可重复集成，这可以实现扩展的设计灵活性和高长期稳定性。为此，需要加强对纺织品结合类型（例如织物编织）与自适应复合结构的最终功能特性之间的相关性的理解。这将导致复合材料中SMA致动器的功能和损伤相关集成概念的开发和设计，以实现高致动力和变形程度和速度。为了扩大SMA的性能和变形潜力，开发了考虑SMA在适应层压复合材料结构中的定位和方向以及结构本身以铰链形式的局部柔性的设计概念。为了预测复合材料结构的动态变形行为，提出了一种基于多尺度建模方法的自适应复合材料结构仿真方法。此时，在结构力学分析中考虑了微观层面上SMA与纺织增强材料之间的摩擦学联系机制以及SMA活化后复合材料中的热生成。为了在结构水平上对自适应复合材料进行有效的建模，复合材料的梯度特性是使用依赖于位置的结构和材料特性来分配的。通过数值模拟，可以推导出自适应复合材料结构功能性能与结构性能之间的结构性能关系。最后，深入了解材料，结构和功能特性，特别是相应的相互作用，使自适应复合材料的有效设计适用于不同的应用领域。

High-performance fiber materials, such as glass fiber and carbon fiber filament yarns, and their textile processing into suitable reinforcing semi-finished products form the foundation for heavy-duty fiber-reinforced polymer composites (FRPC). The functional scope of this material group can significantly extended by the material-specific integration of actuator and/or sensor functions into the composite. Actuator materials in particular, such as shape memory alloys (SMA), show particularly high potential for an active functionalization of composite structures. The aim of the proposed project is the realization of novel shape-variable lightweight structures based on adaptive composites with reproducible and spatially complex deformation behavior. Here, glass fiber textile-reinforced composites with thermoset matrix systems are to be functionalized by positioning and textile integration of yarn- or wire-shaped SMA actuators into the textile reinforcement structure. One of the focuses is on the specific and automated/reproducible integration of the SMA actuators in the composite, which enables an extended design flexibility and a high long-term stability. For this purpose, an enhanced understanding of the correlations between the textile binding type (e.g. fabric weave) and the resulting functional properties of the adaptive composite structure needs to be established. This will lead to the development and design of functional and damage-related integration concepts of SMA actuators in composites to realize high actuating forces and degrees and speeds of deformation. To expand performance and deformation potential of the SMA, design concepts are developed which take into account the positioning and orientation of the SMA in an adapted laminate composite structure and the local flexibility of the structure itself in form of hinges. For the prediction of the dynamic deformation behavior, a simulation methodology based on multi-scale modelling approaches is developed to model and design the adaptive composite structure. At this point, the tribological linkage mechanisms between SMA and textile reinforcement at micro level as well as the heat formation in the composite due to the activation of the SMA are considered in the structural mechanical analysis. With regard to an efficient modelling of the adaptive composite at structural level, the graded properties of the composite are assigned using location-dependent structural and material properties. With the numerical simulation, the structure-property relationships between functional and structural properties of adaptive composite structures can be derived. Finally, the gained in-depth understanding of material, structural and functional properties and, in particular, corresponding interactions enables an efficient design of adaptive composites for different fields of application.