Analytical and Simulation-Based Prediction of Surface Roughness for Micromilling Hardened HSS

Abstract

The high quality demand for machined functional surfaces of forming tools, entail extensive investigations for the adjustment of the manufacturing process. Since the surface quality depends on a multitude of influencing factors in face micromilling, a complex optimization problem arises. Through analytical and simulative approaches, the scope of the experimental investigation to meet the requirements for surface roughness can be significantly reduced. In this contribution, both analytical and simulation-based approaches are presented in the context of predicting the roughness of a machined surface. The consideration of actual tool geometry and shape deviations are used in a simulation system to achieve the agreement with experimental results.

Modeling of cutting forces in trochoidal milling with respect to wear-dependent topographic changes

“…The tool model is based on a structured grid which allows for an accessible assignment of isolated cutting segments along the tool [26]. The structured grid can be implemented as a triangular mesh, which enables numerically stable intersection tests with discrete workpiece representations [27]. The workpiece is modelled by using three perpendicular dexelboards, each with a defined spatial precision.…”

Simulation-Based and Experimental Investigation of Micro End Mills with Wiper Geometry

“…The introduced tool concept was investigated using a simulation-based approach in advance to reveal the first dependencies and to restrict the selection of suitable tool modifications for the experimental investigation. For a prediction of the resulting surface topographies with the new tool geometry, a geometrical material removal simulation (MRS) was used [ 20 ]. This approach made use of a heightfield as the workpiece representation and a triangle mesh as the tool model, in which the microgeometry of the cutting edges could be included in high resolution.…”

“…With a time-based discretization of NC milling paths and the rotational speed, discrete substeps of the engagement situations are calculated and the material removal can be simulated via triangle ray intersection tests. The validation of this simulation approach for an application in the field of micromachining was presented in [ 20 ].…”

“…The surface roughness of components is an important criterion that clearly determines the later operational behavior of machined functional surfaces [ 19 ]. In addition to material-specific effects, the manufactured surface topography of the workpieces and thus the resulting roughness is mainly determined by the engagement conditions [ 20 ]. The latter is predominantly defined by the cutting parameters, such as feed per tooth, f z , depth of cut, a p , and width of cut, a e , and the tool design (see Figure 1 ).…”

“…A detailed examination of the resulting roughness peaks illustrates the dependency to process as well as geometric tool characteristics ( Figure 1 c). In previous research, such considerations of the engagement situation and material residue resulted in several analytical models that estimate the theoretical maximum roughness depth, Rth , for different machining processes on the basis of the engagement situation, which was characterized by e.g., tool and process parameters [ 20 , 21 , 22 , 23 ].…”