Auslegung und Optimierung von gefügten SLM-Bauteilen

Research output: ThesisMaster's Thesis

Abstract

Additive manufacturing is a disruptive technology in the manufacture of machine components - new ways of thinking in development and construction are possible. Selective laser melting (SLM) is of special importance for machine components and series components, whereby the maximum component size is limited by the dimensions of the process chamber. Due to the nature of the process, materials used for this process can be welded well, which means that the geometrical limitations of the process chamber can be compensated by several welded individual SLM components. In this thesis, the performance of the SLM process for larger structures is assessed. As an example of this, a motorcycle frame for an existing series motorcycle is being developed. The existing vehicle architecture and existing stiffness targets serve as a starting point for an optimization aimed at the combination of SLM printing and welding as a potential manufacturing process for a small serial production. The optimization of the frame consists of a material selection, topology optimization and the segmentation of the frame into optimally printable individual parts. By referencing the series frame, it becomes clear whether and how well the frame can be specifically optimized for the defined parameters with the combination of topology optimization and additive manufacturing, whereby a reduction in weight has been achieved. The redesign of the topology optimization result is validated with a numerical stress analysis. Findings from this simulation flow into the result through manual shape optimization. For the division of the frame into printable individual parts, on the one hand the numerically determined stresses are important and, on the other hand, an attempt is made to design the division ideally in terms of avoiding support structures and utilizing the installation space. To be able to assess effects of the weld seams on fatigue properties, selected weld seam geometries are numerically analyzed and evaluated, based on the effective notch stress concept according to the IIW guideline. Depending on the weld seam geometry, the results show a reduction in service life from 95 % up to 99 %, with local weld seam imperfections, such as undercuts, showing a significant influence on the service life behavior.

Details

Translated title of the contributionDesign and optimization of joined SLM-components
Original languageGerman
QualificationDipl.-Ing.
Awarding Institution
Supervisors/Advisors
Award date23 Oct 2020
Publication statusPublished - 2020