Effect of Volumetric Energy Density and Part Height on the Material Properties of Low-Alloyed Steels Manufactured by Laser-Based Powder Bed Fusion of Metals

Bartels D, Novotny T, Albert M, Mohr A, van Soest F, Hill H, Merklein C, Schmidt M (2023)

Publication Type: Journal article

Publication year: 2023

Journal

Advanced Engineering Materials Wiley

DOI: 10.1002/adem.202300009

Abstract

The layer-by-layer manufacturing approach in laser powder bed fusion of metals (PBF-LB/M) leads to heat accumulation in the workpiece with increasing part heights. The effect of this heat accumulation on the resulting material properties has, however, only barely been studied for low-alloyed steels. The goal of this work is to analyze the influence of different PBF-LB/M-specific boundary conditions like varying part heights and volumetric energy densities (VED) on the resulting material properties. It isfound that lower part regions possess similar hardness (380–410 HV1) and retained austenite values (7%–8%), independent of the applied VED. Higher energy inputs lead to higher retained austenite contents of up to 20% due to an incomplete transformation upon cooling. This rise in retained austenite content is also linked to a decreased material hardness down to 320 HV1. In higher part regions, this effect is reversed as the retained austenite content starts to decrease for the highest investigated VED. This is caused by the in situ preheating temperatures caused by heat accumulation, which favor a bainitic transformation. The part height-specific properties indicate that the microstructure formation forms through a continuous transformation in lower part regions and through an isothermal transformation in higher regions.

Authors with CRIS profile

Dominic Bartels Lehrstuhl für Photonische Technologien Michael Schmidt Lehrstuhl für Photonische Technologien

Additional Organisation(s)

FAU Profilzentrum Licht.Materie.Quantentechnologien (FAU LMQ)

Involved external institutions

Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG DE Germany (DE) Schaeffler Technologies AG & Co. KG DE Germany (DE)

How to cite

APA:

Bartels, D., Novotny, T., Albert, M., Mohr, A., van Soest, F., Hill, H.,... Schmidt, M. (2023). Effect of Volumetric Energy Density and Part Height on the Material Properties of Low-Alloyed Steels Manufactured by Laser-Based Powder Bed Fusion of Metals. Advanced Engineering Materials. https://dx.doi.org/10.1002/adem.202300009

MLA:

Bartels, Dominic, et al. "Effect of Volumetric Energy Density and Part Height on the Material Properties of Low-Alloyed Steels Manufactured by Laser-Based Powder Bed Fusion of Metals." Advanced Engineering Materials (2023).

BibTeX: Download