Investigation of Material Properties of Wall Structures from Stainless Steel 316L Manufactured by Laser Powder Bed Fusion
Hoang Minh Vu,
Steffen Meiniger,
Björn Ringel,
Holger Claus Hoche,
Matthias Oechsner,
Matthias Weigold,
Matthias Schmitt,
Georg Schlick
Affiliations
Hoang Minh Vu
Mechanical Engineering, Center for Structural Materials, State Materials Testing Institute Darmstadt (MPA), Chair and Institute for Materials Technology (IfW), Technical University of Darmstadt, 64283 Darmstadt, Germany
Steffen Meiniger
Mechanical Engineering, Institute for Production Management, Technology and Machine Tools (PTW), Technical University of Darmstadt, 64287 Darmstadt, Germany
Björn Ringel
Additive Manufacturing, Processing Technology, Fraunhofer Institute for Casting, Composite and Processing Technology (IGCV), 86159 Augsburg, Germany
Holger Claus Hoche
Mechanical Engineering, Center for Structural Materials, State Materials Testing Institute Darmstadt (MPA), Chair and Institute for Materials Technology (IfW), Technical University of Darmstadt, 64283 Darmstadt, Germany
Matthias Oechsner
Mechanical Engineering, Center for Structural Materials, State Materials Testing Institute Darmstadt (MPA), Chair and Institute for Materials Technology (IfW), Technical University of Darmstadt, 64283 Darmstadt, Germany
Matthias Weigold
Mechanical Engineering, Institute for Production Management, Technology and Machine Tools (PTW), Technical University of Darmstadt, 64287 Darmstadt, Germany
Matthias Schmitt
Additive Manufacturing, Processing Technology, Fraunhofer Institute for Casting, Composite and Processing Technology (IGCV), 86159 Augsburg, Germany
Georg Schlick
Additive Manufacturing, Processing Technology, Fraunhofer Institute for Casting, Composite and Processing Technology (IGCV), 86159 Augsburg, Germany
To make powder bed fusion (PBF) via laser beam (-LB) for metals (/M) available for highly regulated components such as pressure equipment according to the Pressure Equipment Directive, system-specific qualification methods need to be established to deal with process- and geometry-dependent inhomogeneous material behavior. Therefore, the material properties of austenitic stainless steel (316L) and their influences on normative acceptable qualification strategies were investigated in this study. Flat tensile test specimens were produced by two manufacturing systems identical in construction and were compared to specimens produced from conventionally rolled sheet material. Specimens were compared in the horizontal and vertical building directions in relation to different slope angles, wall thicknesses and cross-sectional areas. Despite identical process setups, parameters and powder feedstock, differences in mechanical behavior could be seen. Furthermore, the mechanical properties, surface roughness and density showed dependencies on the wall thickness and slope angle. In particular, the influence of wall thickness has not been covered in publications about PBF-LB/M before. These results suggest that geometry- and system-dependent components can be designed based on associated data from qualification processes. Therefore, a new qualification method based on wall structure properties is suggested for standard qualification processes of components with wall structures, such as pressure equipment.
