Bulk metallic glasses (BMGs) offer exceptional physical/mechanical properties enabling them to be highly desirable for a varietyof applications. Laser powder bed fusion (LPBF) has great promise for producing large and intricate BMG structures. However, using non-optimal energy distribution in current additive manufacturing machines leads to extensive reheating of previously solidified layers. As a result, the mechanical characteristics can be significantly impacted by structural relaxation and partial crystallization. Here, a tunable advanced laser beam shaping technology is employed to overcome the difficulties originating from non-optimal energy distribution in current additive manufacturing machines. This study fabricates fully amorphous/dense BMG samples using the shaped laser beam and established optimized atomic-scale short-and medium-range ordering along with improved yield/fracture compressive strength. Formation of a shallow and wide melting pool geometry using the beam shaping allows to increase hatching distances to better control the thermal history introducing improved amorphicity and rejuvenation. This higher rejuvenation and disordering allow for increased atomic mobility, which facilitates the creation and spread of shear bands, thus enhancing the mechanical strength and ductility of the material. The current work demonstrates that BMG parts can be fabricated using flexible beam-shaping technology allowing to go beyond the capabilities of state-of-the-art additive manufacturing techniques.
Bibliographische NotizFunding Information:
The authors sincere gratitude goes out to Heraeus AMLOY Technologies to support the project by supplying commercially available AMLOY ZR01‐powder for the 3D‐printing tests. The core technology platform for the beam shaping experiments was developed in the frame of the innovation project SLM. The authors would like to express the sincere gratitude to Irpd AG (Switzerland) for their valuable support and contributions in terms of time, expertise, and resources; and to Innosuisse, the Swiss Innovation Agency for funding under Grant No. 40570.1. The authors would like to thank Dr. Anton Hohenwarter for his invaluable support throughout the mechanical properties experiments. Special thanks to Fabio Aebischer for his design and graphical supports and inputs.The authors thank DESY (Hamburg, Germany), a member of the Helmholtz Association (HGF), for providing experimental facilities. Parts of this research were carried out at PETRA III using the Powder Diffraction and Total Scattering beamline P02.1 and the authors would like to thank the Beamline Scientist Alba S. J. Méndez, Miguel Brito Costa, and Nizhen Zhang for experimental assistance. Beamtime was allocated under proposal I‐20220565 EC. 2
© 2023 The Authors. Advanced Functional Materials published by Wiley-VCH GmbH.