Modelling of broaching processes by multi scale discretization

 

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.