Development of a three-dimensional finite element method simulation model to predict modified flow drilling tool performance

Flow drilling is a relatively unexplored manufacturing process in which the tool penetrates the workpiece with a defined force or defined feed along its rotational axis. This paper presents a developed three-dimensional (3D)-finite element method (FEM) simulation model to predict the performance of modified flow drilling tools. To validate the simulation model, the flow drilling of AlSi10Mg with a non-pre-heated (T_initial = 20 °C) and pre-heated (T_influenced = 200 °C) tool was investigated. Thereby, the comparison of measured and simulated values of temperature, force and torques showed a good agreement. The comparison of the forces and torques concluded in almost identical maximum values. Nevertheless, the pre-heated tool was found to have a significantly more continuous heat distribution and higher bore quality than non-pre-heated flow drills, which can be attributed to the better formability of the cast aluminum alloy at elevated temperatures. Since the results of the simulation showed a good agreement with the experimental values, the three-dimensional model was used to predict the process behavior of a modified flow drilling tool, which could contribute to the optimization of the process. The result show, that the process time could be reduced by half, while the occurring temperatures, forces and torques remained acceptable.