This paper discusses the influence of geometry recovery on actual stress fields within load-carrying parts that have to be reconstructed from the resulting surfaces obtained by topology optimization procedures. A typical result of a topology optimization process is a triangulated surface which represents the boundary of the optimized part. In a production environment, this triangulated surface is mostly used to reconstruct a proper CAD model of the optimized part. This process is by far not automated and may require significant skills and efforts. Unfortunately, it also unavoidably introduces variations in the geometry of the optimized part. Although visually these variations might seem to be rather minor, they may very quickly introduce significant stress field variations. These variations may result in harmful locally increased stress levels and even significant stress concentrations. To get more insight into these phenomena, the topology of a quasi-two-dimensional example part is optimized. The resulting geometry is then reconstructed with various levels of precision. For the obtained geometries, the stress fields are studied numerically. It is shown that stress field variations are indeed such that they may influence significantly the probability of fatigue crack initiation and consequently the service life of the part. Obviously, the geometry recovery after topology optimization should be done very carefully, especially if the part will be subject to cyclic loading during operation.
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