This study aims to review multi-material three-dimensional (3D) printing by laser powder bed fusion (LPBF) process. Advancements in the LPBF process for multi-material 3D printing of different metallic alloys, focusing on material pre-alloying and chamber refilling approaches to achieve functionally graded and multi-layered compositions, have been presented.
The methodology involved an in-depth analysis of prominent research and peer-reviewed publications related to multi-material 3D printing using LPBF. A database of the Web of Science from the previous 20 years was examined using VOSviewer software for bibliometric analysis to identify research gaps. A networking diagram highlighting the research gap was generated using the study’s obtained relevance score. A case study was conducted for a single-hopper-based LPBF process for multi-material 3D printing of metals, exploring two novel approaches: material pre-alloying and chamber refilling to control material composition and layering with a single hopper.
A comprehensive review of multi-material 3D printing by LPBF, followed by a case study, highlights the challenges and advances in single-hopper-based LPBF for multi-material 3D printing of metallic components, focusing on innovative methods (material pre-alloying and chamber refill) to enable compositional gradients and layered structures. A functionally graded material (FGM) comprising 17–4 precipitate-hardened (PH) stainless steel (SS) and Ni625 was successfully 3D printed using chamber refill and material pre-alloying in a single-hopper LPBF system. However, a few limitations apply to multi-material 3D printing using LPBF, including managing phase evolution, mechanical characteristics and material compatibility. Integrating machine learning and AI-driven process optimization can enhance predictive capabilities and facilitate compelling exploration of process parameters to achieve desired material performance and structural integrity.
This study provided a comprehensive review of multi-material 3D printing using the LPBF technique and discussed a novel single-hopper multi-material 3D printing approach as a case study. This review offers insights into the maintenance and operation of single-hopper LPBF machines as an operational resource for industry/ academia for multi-material printing.
