Scaling and Transfer Effects in Reactive Materials

该项目旨在通过反应多层膜的二维和三维结构来定义控制或减缓反应材料形成的基本规则。将研究反应多层膜的结构元素的横向尺寸、空间布置和几何形状对点火行为、反应前沿的传播速度和相形成的影响。在无限维平面二元反应多层膜中，控制反应速率的最重要参数是材料组合、双层膜厚度、单层膜厚度及其微结构。发生的内在应力，这是未来设备的可靠设计的关键，将确定热机械耦合的数值模拟和参数识别的逆建模。该项目将回答以下问题：横向和垂直约束以及相关反应路径对定制形态的影响是什么？如何利用自由表面和局部调节热导率的材料环境来控制反应路径和形态？形态学的局部变化对反应的影响是什么？它们能用于过程控制吗？反应多层膜的结构如何影响反应和热传播？如何通过应用定义的基本规则来控制连接过程和机械性能？该项目专注于缩放和转移过程，与“相场模拟和实验微观结构研究”和“反应连接过程的定制热释放特性”合作，为研究和制定基本规则做出贡献，作为将反应材料集成到不同应用领域的连接技术中的先决条件。

This project aims at defining fundamental rules to control or slow down the formation of reactive materials by two and three dimensional structuring of the reactive multilayers. The effect of the lateral dimension, the spatial arrangement, and the geometrical shape of the structured elements of the reactive multilayers on the ignition behavior, the propagation velocity of the reaction front, and the phase formation will be investigated. In flat binary reactive multilayers with infinite dimen-sion, the most important parameters controlling the reaction rate are the material combinations, the bilayer thickness as well as the thickness of the individual layers and their microstructures. The occurring intrinsic stresses, which are critical for a reliable design of future devices, will be identified by thermomechanical coupled numerical simulations and parameter identification by inverse modelling. The project will answer the following questions: What is the effect of lateral and vertical confinements and the related reaction path on the tailored morphology? How can free surfaces and a materials environment of locally adjusted thermal conductivities be exploited to control the reaction path and the morphology? What is the effect of local changes in the morpho-logy on the reaction and can they be used for the process control? How does the structuring of reactive multilayer affect the reaction and heat propagation? How can the joining process and mechanical properties be controlled by applying the defined fundamental rules? Focusing on scaling and transfer processes the project contributes in cooperation with “Phase field simulation and experi¬mental microstructure research” and “Tailored heat release characteristics for reactive joining processes” to the investigation and formulation of fundamental rules as a precondition of the in¬tegration of reactive materials into joining technology for different application fields.