Defined cutting edge preparation for process optimization in micro milling

微铣削工艺具有目标几何复杂、材料范围广、经济潜力大等特点。微铣刀失效的一个原因通常是切削刃的磨损，这是切削材料时高负荷的结果。定义的切削刃制备提供了稳定切削刃和减少磨损的方法。其结果是更高的刀具寿命和工艺稳定性。整个项目的目的是通过使用刀具的制备，优化微铣刀，从而改进微铣削工艺。在实验和模拟中探索和确定浸入式翻滚的最佳工艺参数和加工策略，这在工业上也被称为拖曳整理。通过对制备微铣刀和未制备微铣刀的磨损分析，获得与工艺条件相关的最佳切削刃几何形状的基本知识。在第一个资助期内，一开始就制定了微铣刀的计量分析策略。随后，对定义的刃口制备进行浸入式翻滚工艺参数分析，并建立回归模型。此外，通过磨损和切削力分析确定了提高工艺安全性的切削刃几何形状，并开发了创建浸入式翻滚模拟预测模型的基础。在第二个资助期内，将完成预测模型，并对浸入式翻滚的几何变化进行数值计算。此外，将对各种刀具涂层进行表征，并确定涂层对切削刃几何形状的影响。本资助期的目标是探索和确定浸入式滚压对涂层进行预处理和后处理的加工策略。一种优化的涂层制备方法是减少切削刃的剥落，增加涂层与切削刃的附着力。刀具后处理的目的是去除电弧PVD涂层过程中刀具表面不需要的液滴。通过对磨损和切削力的分析，将获得关于所生成的切削刃几何形状在工艺条件下的行为的知识，并最终将两个资助期的实验结果用于确定优化的涂层预处理和后处理策略。

The micro milling process is characterized by a target geometric complexity, a wide range of materials and a large economic potential. One reason for the failure of micro milling tools is usually the wear of the cutting edges, which occurs as a result of high loads when cutting the material. A defined cutting edge preparation provides an approach to stabilize the cutting edge and to reduce wear. The result is higher tool life and process stability.The aim of the overall project is the improvement of the micro milling process by optimizing the micro milling tools through using the preparation of the cutting tool. In the foreground is the experimental and simulative exploration and definition of the optimal process parameters and processing strategies of the immersed tumbling which is also known as drag finishing in the industry. By wear analysis of respectively prepared and unprepared micro milling tools, basic knowledge about the optimal cutting edge geometry in dependence of the process conditions will be obtained.In the first funding period, a strategy for metrological analysis of micro milling tools was worked out at the beginning. Subsequently, the process parameters in the immersed tumbling were analyzed for the defined cutting edge preparation and a regression model was generated. Furthermore, cutting edge geometries for increased process safety were identified by wear and cutting force analyses and the basics for the creation of a predictive model for the simulation of immersed tumbling were developed.In the second funding period, the prediction model will be completed and a numerical calculation of the geometrical change in the immersed tumbling will be made. Furthermore, various tool coatings will be characterized and the resulting change of the cutting edge geometry by coating will be determined. The objective of this funding period is the exploration and definition of machining strategies for the pre-processing and post-processing of coatings by the immersed tumbling. An optimized coating preparation is to reduce the chipping of the cutting edge and increase the coating adhesion to the cutting edge. The aim of the tool post-processing is the removal of unwanted droplets on the tool surface which occur during coating by arc PVD. Through the wear and cutting force analysis, knowledge about the behavior of generated cutting edge geometries depending on the process conditions will be obtained and finally the experimental results of both funding periods will be used for the definition of optimized pre-processing and post-processing strategies of coatings.