Parameter identification approach for support structures in laser powder bed fusion and analysis of influencing factors

Additive manufacturing, especially laser powder bed fusion (LPBF), enables the build-up of complex parts. LPBF is a technology with high geometric degrees of freedom, but there are production restrictions, e.g. with regard to overhangs. One strategy to produce these components despite the restrictions is the use of support structures. Parameter determination for support structures is strongly neglected in contrast to component parameters. In this paper, a methodology for determining parameters for support structures is presented. Test geometries for the determination of mechanical properties (tensile and torsional properties) are developed. Subsequently, the influence of the manufacturing parameters (e.g. laser power) on the properties of the widely used lattice support are determined for the case-hardening steel 16MnCr5. It can be shown that shear and tensile strength of the support structures are influenced by the applied manufacturing parameters. Furthermore, the influence of geometrical parameters such as grid spacing and perforation on the tensile strength is investigated.