Papers by Keyword: Geometry Influence

Abstract: In contrary to the traditional injection molding process, the selective laser sintering process offers a nearly unlimited freedom of design. However, the dimensional accuracy of an SLS part is significantly influenced by the process, the material and its design. In order to achieve high accuracy, the parts need to be repositioned, parameters readjusted and parts consistently rebuilt in an iterative process. In industry this process leads to enormous consumption of process time and polymer powder.Increased dimensional inaccuracy is often caused by the accumulation of polymer melt and the resulting shrinkage effects. Thus, highly accurate SLS parts can be manufactured using three dimensional, filigree structures in order to replace volumetric part sections. In this paper, the potential of using 3D-structures, for enhancing SLS parts’ accuracy is shown. Thus, influencing parameters, such as positioning, scale, process time and geometry feature are systematically varied. Additionally the effect of adjacently positioned parts influencing the dimensional accuracy shall be investigated.

Abstract: The paper investigates the mechanical properties of sintered hollow sphere struc- tures. First of all, the Young's modulus, plastic modulus, initial flow stress, initial flow strain, plateau stress and densifcation strain are derived from compressive tests. In addition, the material behaviour during the compressive testing is described. Furthermore, the influence of different specimen shapes on the results is discussed.