Basic research on the immersed tumbling process using magneto-rheological fluid for the specific cutting edge preparation of milling tools – RheoTumble

近几年和几十年来，微型和精密零部件的高效生产变得非常重要。微细加工是微细加工的核心部分。由于零件的几何和尺寸精度的要求，需要特殊的刀具准备才能进行可靠的加工。切削刃的制备是这一过程中的重要一步。最常用的工艺包括磁力抛光和浸没滚筒。然而，这两种方法都有与过程相关的缺点。例如，不可能实现局部定义的加工压力和材料分离，这大大限制了准备工作。这些缺点可以通过这两个过程的组合来克服。因此，该研究项目的总体目标是为浸没滚流与磨料磁流变液(MRF)的组合应用产生和提供基础知识。因此，要优化的磨料磁流变液在恒定的时空条件下以及动态变化的磁场下应用于硬质合金微细铣刀的特定刃口制备。为了实现这一总体目标，正在开发和实施一种使用磨料磁流变液进行浸没滚流的创新装置。该设备能够在生产环境中研究磨料磁流变液的流变性、磨料特性和流动特性。为此，首先对简化的正方形几何进行了基本研究。在已有知识的基础上，建立了有限元、CFD和DEM耦合模型，用于解释和优化试验研究结果。最后，给出了工业环境下磨料磁流变液在微细铣刀浸没滚流中的应用技术和策略。作为研究项目的结果，基本的科学发现使基于磨料磁流变液的浸入滚流过程能够得到明确的控制，用于制备工业应用中的硬质合金微细铣刀的刀具刃口。在集成到机床上的基础上，研究项目实现后，可以显著减少总加工时间Tg。

The efficient production of micro and precision components has gained considerably in importance in recent years and decades. Micro milling is a central part of micro manufacturing. Due to the requirements for geometrical and dimensional accuracy of the components, special tool preparation is required for reliable machining. The preparation of the cutting edges is an important step in this process. The most frequently used processes include magnetic finishing and immersed tumbling. However, both methods have process-related disadvantages. For example, it is not possible to realize locally defined machining pressures plok and material separations, which significantly limits the preparation. These disadvantages can be overcome by a combination of both processes. Therefore, the overall objective of the research project is the generation and provision of fundamental knowledge for the combined application of immersed tumbling with abrasive magnetorheological fluids (MRF). Thereby, an abrasive MRF to be optimized is applied under constant spatial-temporal conditions as well as by dynamically changed magnetic fields for the specific cutting edge preparation of micro-milling tools made of cemented carbide. In order to achieve the overall objective, an innovative device for immersed tumbling using abrasive MRF is being developed and implemented. The device enables the investigation of the rheological, abrasive and flow properties of abrasive MRF in a production environment. For this purpose, basic investigations are first carried out on simplified square geometries. Based on the gained knowledge, a coupled FEM-, CFD- and DEM-model is developed required to interpret and optimize the results of the experimental investigation. Finally, technologies and strategies for the use of abrasive MRF in the immersed tumbling of micro-milling tools in an industrial environment are derived. As a result of the research project, fundamental scientific findings are available enabling a well-defined control of the immersed tumbling process based on abrasive MRF for the preparation of cutting edges of cemented carbide micro-milling tools in industrial applications. Based on the integration into machine tools, a significant reduction of the total machining time tG can be achieved after realization of the research project.