Modelling of broaching processes by multi scale discretisation

在拉削过程中，工艺参数直接在刀具中确定，因此必须在设计阶段确定。必须根据刀具和工件的材料组合来决定齿距、每齿升程以及齿的宏观和微观几何形状。这些设计参数显著影响生产率、切屑形成、刀具磨损和切削力，而实验优化成本非常高。因此，拉刀大多被设计为故障安全的，即使根据热机械工具负载，机床和工件要求的设计不是最优的。这个项目的目标是开发一个多尺度模型来模拟拉削过程。该方法旨在显示和计算过程、工具和机床之间的相关相互作用。因此，拉刀和工艺可以在刀具负荷、生产率和制造成本方面进行有效的设计。该模型由多个子模型组成，将拉削过程在不同的时空尺度上离散化。这使得将中尺度切屑形成模型的精度与宏观过程和机器模型相结合成为可能。

In broaching, the technological process parameters are directly ground in the tool and therefore have to be defined in the design stage. Decisions about the tooth pitch, the rise per tooth and the tooth macro- and microgeometry have to be made according to the tool and workpiece material combination. These design parameters significantly influence the productivity, chip formation, tool wear and the cutting forces and experimental optimizations are very expensive. On this account, broaches are mostly designed fail-safe, even if the design is not optimal according to the thermal mechanical tool load, machine tool and workpiece requirements. The goal of this project is the development of a multiscale model to simulate the broaching process. The approach is supposed to show and calculate relevant interactions between process, tool and machine tool. Therefore, the broach and the process can be designed efficiently in terms of tool load, productivity and manufacturing costs. The model consists of several submodels to discretize the broaching process in different spatial and temporal scales. This makes it possible to combine the precision of a mesoscale chip formation model with a macroscopic process and machine model.