Degradation of AlSi10Mg powder during laser based powder bed fusion processing
Journal article, 2021

Knowledge concerning powder degradation during additive manufacturing (AM) processing is essential to improve the reusability of the powder in AM and hence maximize feedstock powder reuse and economy of the process. AlSi10Mg powder degradation in Concept Laser XLINE 2000R machine over the total period of 30 months was analyzed in order to understand the extent and mechanism affecting powder aging. Thereby, detailed analysis of the powder morphology, microstructure and surface chemistry was performed by SEM, TEM and XPS. The results show an increase in volume fraction of heavily oxidized spatter particles up to 3% in 30 months. XPS analysis of the powder surface chemistry indicates that powder particles are covered by uniform oxide layer, formed by Mg- and Al-based oxides, average thickness of which increased from ~4 nm in case of the virgin powder up to about 38 nm in case of the reused for about 30 month powder, established by XPS. Analysis of the oxide characteristics were consistent with the observed oxygen content in the sampled powder. Columnar oxide scale formation on spatter particles was revealed as well, reaching up to 125 nm in thickness measured using STEM. Results of the XPS and STEM-EDX analysis of oxide composition are shown to be in agreement with the thermodynamic calculations confirming that oxide scale on sputter particles is formed by MgAl2O4 spinel and Al2O3 (corundum) oxides.

Laser based powder bed fusion

AlSi10Mg powder

Additive manufacturing

Reused powder in AM

Powder degradation

Spatter particles

Author

Ahmad Raza

Chalmers, Industrial and Materials Science, Materials and manufacture

Tobias Fiegl

Neue Materialien Fürth GmbH

Imran Hanif

Chalmers, Chemistry and Chemical Engineering, Energy and Material

Andreas MarkstrÖm

Thermo-Calc Software AB

Martin Franke

Neue Materialien Fürth GmbH

Carolin Körner

University of Erlangen-Nuremberg (FAU)

Eduard Hryha

Chalmers, Industrial and Materials Science, Materials and manufacture

Materials and Design

0264-1275 (ISSN) 1873-4197 (eISSN)

Vol. 198 109358

Subject Categories

Ceramics

Materials Chemistry

Metallurgy and Metallic Materials

DOI

10.1016/j.matdes.2020.109358

More information

Latest update

12/21/2020