Application of the polyurethane spraying process on the large scale production of fibre-reinforced structural components with sandwich elements for IT-transportation systems

以聚氨酯（PU）为基体的复合材料制成的高性能部件已在许多工业应用中证明了其经济潜力。因此，聚氨酯的快速交联动力学对材料的成功起着决定性的作用。然而，生产部件的缺点是纤维体积含量低，使用发泡PU。连续纤维纺织品的pu喷雾浸渍（树脂喷雾预浸（RSP））领域的发展，结合联合研究项目知识（FOR860）范围内的优化成型和固化工艺，可以在短周期内生产高纤维体积含量（bbb50 %）的自动化高性能部件。到目前为止，生产技术只对简单的几何形状进行了分析。因此，应用项目的目的是将FOR860的知识在短周期内生产高性能复合材料部件，以生产高应力夹层结构。对于特定产品的实施，需要进一步的科学研究。由于其复杂性，这些研究只有通过工业企业和研究机构之间的跨学科合作才能实现。在FOR860的范围内，结果表明，在调整后的工艺技术和工业制造设备下，在短周期内生产夹层零件的高应力顶层是可能的。为了确保该工艺在工业中被接受，高应力连续纤维增强顶层应首先与该工艺中生产的常用的具有成本效益的纸蜂窝或泡沫芯相结合。因此，应根据FOR860的研究结果对系统技术进行改进，使夹层结构可以一步生产，并可根据树脂反应性和泡沫反应进行工艺调整。考虑到工艺参数，随后应分析所生产零件的特性，例如表面质量、声学特性和力学值。在对平面零件进行基础研究之后，应该将知识转移到轻量级IT运输箱的生产中（图）。所选择的用于调查的演示部件的几何形状允许将结果转移到大面积部件（例如商用车辆或火车）以及其他消费品领域的应用中。

High performance parts made from composites with a polyurethane (PU) matrix have proven their economic potential in many industrial applications. Therefore, the fast cross-linking kinetics of the PU have played a decisive part in the success of the material. However, the disadvantages of the produced parts are the low fibre volume content and the use of foamed PU. The developments in the field of PU-spray impregnation of continuous fibre textiles (Resin Spray Prepregging (RSP)) in combination with an optimised forming and curing process within the scope of the joint research project knowledge (FOR860) allow to produce automated high performance parts in short cycle times with high fibre volume contents (> 50 %). Up to now, the production techniques have only been analysed for simple geometries. Therefore, the aim of the applied project is the transfer of the FOR860 knowledge to produce high performance composite parts in short cycle times to the production of highly stressed sandwich structures. For an implementation of specific products, further scientific investigations are necessary. Because of the complexity, these investigations are only feasible by interdisciplinary cooperation between industrial companies and research institutes. Within the scope of the FOR860, the results have shown that the production of highly stressed top layers for sandwich parts in short cycle times with an adjusted process technology and an industrial manufacturing equipment is possible. To ensure an acceptance of the process in the industry, highly stressed continuous fibre reinforced top layers should be initially combined with commonly used cost-effective paper honeycomb or foam cores produced in the process. Therefore, the system technology should be modified based on the findings of the FOR860, so that the sandwich structures can be produced in one step and the process can be adapted according to the resin reactivity and the foam reaction. Taking into account the parameters of the process, the characteristics of the produced parts should be analysed afterwards, e. g. surface quality, acoustic properties and mechanical values. Subsequent to fundamental investigations on planar parts, the knowledge should be transferred to the production of a lightweight IT transportation case (figure). The selected geometry of the demonstration part for the investigations allows a transfer of the results to large-area parts (e. g. in commercial vehicles or trains) as well as to applications in the field of other consumer goods.