Title: Design rule for efficient support connection point spacing in laser powder bed fusion of Ti6Al4V

DOI: https://doi.org/10.15480/882.9625

Authors: 
Asami, Karim, ORCID ID: 0000-0001-8382-263X,

Affiliation: Hamburg University of Technology, Institute of Laser and System Technologies;
 
Bartsch, Katharina, ORCID ID: 0000-0002-2572-4596,

Affiliation: Fraunhofer Institute for Additive Production Technologies; 

Emmelmann, Claus, ORCID ID: 0009-0008-4698-2077,

Affiliation: Hamburg University of Technology, Institute of Laser and System Technologies

The production of additively manufactured components requires the use of support structures to prevent the molten material from sinking in the event of overhangs, to fix the component on the build platform and to minimize residual stresses. However, as support structures are not part of the functional component, resource-efficient use is crucial. The aim is to reduce the volume of the support structures without compromising their function. In this study, cylindrical support structures made of Ti6Al4V were investigated in order to experimentally determine physical limits such as the maximum distance between connection points. Influencing factors such as structure diameter, structure spacing, overhang angle and process parameters were analyzed. Optical measurements provided information on the dimensional accuracy and porosity of the samples, allowing the properties of the support structures to be evaluated. Based on the empirical data, a design guideline in the form of a process map was developed to guide the user to suitable combinations. This guideline can later also be integrated as a numerical rule in the computer-aided generation of support structures. The production of additively manufactured components requires the use of support structures to prevent the melt from sinking in the event of overhangs, to fix the component on the build platform and to minimize residual stresses. However, as support structures are not part of the functional component, a resource-efficient process is required.

The varied parameters are: support distance, support diameter, and overhang angle. The target parameter is the component thickness which has to be 1 mm as designed.