New production technologies in aerospace industry - 5th machining innovations conference (MIC 2014) a new approach to build a heat flux model of milling processes

During the finishing milling process of thin-walled workpieces, deformations occur due to the mechanical and thermal influences. Hence, the manufacturing quality may be affected. The aim of a research project at the iwb is to simulate thermally caused deformations and deriving methods to reduce them. Two approaches subsume the term "reduction methods": The use of less deformation-causing process parameters or alternatively - if this approach is insufficient - To compensate the deformation. Simulating thermally induced deformations necessitates a description of the heat input, which is caused by the milling process. Furthermore, this description needs to be valid for the whole spectrum of process parameters recommended for the used tool. The model of the heat source is based on milling experiments with an in-process measurement of the thermally caused deformations. The experimental results allow differentiating between thermally and mechanically induced deformations due to the restriction on an end milling finishing process. However, these measurements only provide a relation between process parameters (variation of cutting speed feed per tooth and width of cut) and deformations. The simulation model, which will be described within this paper in detail, provides the relation between a variable heat input and its resulting deformations. The experimental and the simulative relations together are leading to a heat source model in dependence of the process parameters.