Investigation of Process-Specific Size Effects by 3D-FE-Simulations

The miniaturization of cutting processes into the micrometer regime shows process-specific size effects like the nonlinear increase of the specific cutting force for decreasing cutting depth. In order to investigate these size effects, the mechanics of the material as well as the operation have to be investigated. A turning process was chosen to study the influence of process parameters like cutting depth h, cutting width b, cutting edge radii r, and cutting velocity v c on the specific reaction force by 3D-Finite-Element-Simulations for normalized AISI 1045. For an adequate numeric reproduction of the material behavior, a physically based rate-dependent plasticity law was used in combination with a failure criterion describing the material damage and chip separation. The characteristics of the influences of the different parameters were analyzed mathematically precisely by similarity mechanics. The characteristics of the chip shapes determined by numerical simulations were compared with experimental results and a good correlation was found. The finite element simulations were executed on the high end mainframe XC4000 for a significant improvement of the run time of the simulations.

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