Production and characterization of complex folded cellular structures made of sheet metal

由金属板材制成的复杂折叠蜂窝结构的生产和表征

• 批准号: 427257349
• 负责人: Professor Dr.-Ing. Mathias Liewald
• 金额: --
• 依托单位: Institut für Umformtechnik (IFU)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/427257349?language=en
• 关键词: Production; characterization; complex; folded; cellular

By folding flat semi-finished products, three-dimensional cellular structures can be produced. Folding structures can be used in various technical fields, especially as sandwich core material between two covering sheets. Sandwich construction methods offer the possibility to put rigid, large-area components into effect. These components have considerable weight and material savings compared to conventional monolithic or differential construction methods.Today’s cellular folding structures can only be produced from initial materials with very small sheet thicknesses (s0 ≤ 0.2 mm). In addition to their use as sandwich elements, folded structures with thicker sheet metals offer considerable potential for the industrial use as cladding elements, crash and carrying structures.The cellular folding cores made of sheet metal are based on isometric folded structures. In the initial state, a mostly flat semi-finished product is formed into repeating unit cells by local bending processes around one or more bending axis orientations (BAO). Bending according to DIN 8582 takes an exceptional position, since the formation of local bending axes enables complex shaping of the workpiece (here the core), which enables an extraordinarily application and application-specific component design. The aim of the research project is the production and characterization of complex cellular structures made of aluminium or steel sheet with thicknesses greater than 0.5mm. For this purpose, a workflow is being developed that covers all aspects from the geometric and structural design to the newly developed production technologies and their technological limits to the manufacture and inspection / quality assurance of optimized structures made of sheet metal in the above-mentioned thickness range. The following sub-targets are addressed in particular: - Development and transfer of analytical design methods for folding thicker sheets - Development of methods for pre-structuring sheet metal - Process development for the production of folded sandwich cores - Modelling of the mechanical properties of sandwich panels and definition of process boundariesThe scientific findings of this project on the one hand enable a more precise estimation of the potential of folded structures made of sheet metal as a new type of core material for two-dimensional sandwich applications and on the other hand extend the basic knowledge on the behaviour and processing of sheet metal in complex, previously unfinished isometric forming processes.

通过折叠扁平半成品，可以生产三维蜂窝结构。折叠结构可用于各种技术领域，特别是作为两个覆盖片材之间的夹层芯材。三明治结构方法提供了实施刚性大面积组件的可能性。与传统的整体式或差动式构造方法相比，这些组件可显着节省重量和材料。当今的蜂窝折叠结构只能由片材厚度非常小的初始材料（s0 ≤ 0.2 mm）生产。除了用作夹层元件外，具有较厚金属板的折叠结构还为工业用途作为包层元件、碰撞和承载结构提供了巨大的潜力。由金属板制成的蜂窝折叠芯基于等距折叠结构。在初始状态下，大部分平坦的半成品通过围绕一个或多个弯曲轴方向（BAO）的局部弯曲工艺形成重复的单元格。根据 DIN 8582 进行的弯曲占据了特殊的地位，因为局部弯曲轴的形成可以实现工件（此处为型芯）的复杂成形，从而实现非凡的应用和特定于应用的组件设计。该研究项目的目的是生产和表征由厚度大于 0.5 毫米的铝或钢板制成的复杂蜂窝结构。为此，正在开发一个工作流程，涵盖从几何和结构设计到新开发的生产技术及其对由上述厚度范围内的金属板制成的优化结构的制造和检验/质量保证的技术限制的所有方面。特别解决了以下子目标： - 开发和转让用于折叠较厚板材的分析设计方法 - 开发预结构化金属板材的方法 - 生产折叠夹层芯材的工艺开发 - 夹层板机械性能的建模和工艺边界的定义 该项目的科学发现一方面可以更精确地估计由金属板材制成的折叠结构作为新型芯材的潜力 另一方面，扩展了有关复杂的、先前未完成的等距成形过程中金属板材的行为和加工的基本知识。