Development, manufacturing, characterisation and modelling of lightweight structures prepared by selective laser melting

该项目的目标是通过获取和科学开发L-PBF（激光粉末床融合）系统来加强轻量化设计的研究领域，用于粉末床中金属结构的近净形状制造。将这种设施纳入现有基础设施可以扩大研究领域，并为后续项目提供更多机会。因此，现有的微观结构分析和力学测试基础设施可以在科学项目的框架内得到更好的利用。该项目旨在开发和增材制造基于AlSi10Mg铝合金的刚度和强度优化的点阵板结构。重点是可以实现高比宏观刚度的晶格拓扑结构，以及细胞壁的屈曲稳定性和基本应力类型的拉、压和剪切的比强度。为了达到这个目的，吸收的细胞壁厚度为0.2 - 0.3 mm，并且壁厚变化尽可能小。利用CT和SEM对生成的点阵板结构进行了分析。对于这些结构的力学研究，除了通常的压缩试验外，还计划使用专门开发的剪切场试验设备进行纯剪切和均匀剪切载荷的循环剪切试验。基于L-PBF系统的研究活动将在轻量化设计能力中心（LLK）进行，将结构和建模能力、材料能力以及设计和制造能力捆绑在一起。可以使用细胞结构和夹层结构的现有专有技术，从而可以以更具可重复性和力流导向的方式生产晶格板结构。在金属基础上增材制造轻量化结构和部件的可能性是兰茨胡特应用科学大学轻量化设计研究领域持续进一步发展的重要先决条件。该设备将在项目期间提供给该大学其他研究领域的科学活动。

The objective of the project is to strengthen the research area of lightweight design by acquiring and scientifically developing an L-PBF (Laser-Powder Bed Fusion) system for the near-net-shape manufacturing of metallic structures in powder beds. The embedding of such a facility into the existing infrastructure enables the expansion of the research area and provides additional opportunities for follow-up projects. Consequently, the existing infrastructure for the analysis of the microstructure and mechanical testing can be better utilised within the framework of scientific projects.The project aims on the development and additive manufacturing of stiffness- and strength-optimized lattice plate structures based on the Al-alloy AlSi10Mg. The focus is on lattice topologies that can achieve high specific macroscopic stiffnesses as well as buckling stability of the cell walls and specific strengths for the basic stress types of tension, compression and shear. For this purpose, a thin cell wall thickness of 0.2 to 0.3 mm with as little wall thickness variation as possible is aspired. The analysis of the generated lattice plate structures is performed by CT and SEM. For the mechanical investigations on these structures, cyclic shear tests with a specially developed shear field test facility for pure and homogeneous shear loads are planned in addition to the usual compression tests. The research activities on the basis of the L-PBF system will be carried out at the Competence Center of Lightweight Design (LLK) by bundling the competences from structural and modeling competence, materials competence and design and manufacturing competence. Existing know-how on cellular structures and sandwich structures can be used, whereby lattice plate structures can be produced in a much more reproducible and force-flow-oriented manner. The possibility of additive manufacturing of lightweight structures and components on a metallic basis represents an important prerequisite for the consistent further development of the research area of lightweight design at the Landshut University of Applied Sciences. The device will be made available to other research areas at the university for their scientific activities during the project period.