In order to investigate the in‐space in situ resource utilization, directed energy deposition (DED)‐based additive manufacturing (AM) has been utilized to process Martian regolith—Ti6Al4V (Ti64) composites. Here we investigated the processability of depositing 5, 10, and 100 wt% of Martian regolith premixed with Ti6Al4V using laser‐based DED, analyzing the printed structure via X‐ray diffraction, Vicker's microhardness, scanning electron microscopic imaging, and wear characteristics utilizing an abrasive water jet cutter to simulate abrasive environments on the Martian surface. The results indicate that the surface roughness and hardness of the composites increase with respect to the Martian regolith’ weight percentage due to in situ ceramic reinforcement. For instance, i5‐wt% addition of Martian regolith increased the Vicker's microhardness from 366 ± 6 HV0.2for as‐printed Ti64 to 730 ± 27 HV0.2while maintaining similar abrasive wear performance as Ti6Al4V. The results point toward laser‐based AM for fabricating Ti64—Martian regolith composites with comparable properties. The study also reveals promising results in limiting the mass burden for future space missions, resulting in cheaper and easier launches.
This content will become publicly available on July 9, 2025
The demand for advanced materials has driven innovation in titanium alloy design, particularly in the aerospace, automotive, and biomedical sectors. Additive manufacturing (AM) enables the construction of multi-material structures, offering potential improvements in mechanical properties such as wear resistance and high-temperature capabilities, thus extending the service life of components such as Ti6Al4V. Directed energy deposition (DED)-based metal AM was used to manufacture radial multi-material structures with a Ti6Al4V (Ti64) core and a Ti6Al4V-5 wt.% B4C composite outer layer. X-ray diffraction analysis and microstructural observation suggest that distinct B4C particles are strongly attached to the Ti6Al4V matrix. The addition of B4C increased the average hardness from 313 HV for Ti6Al4V to 538 HV for the composites. The addition of 5 wt.% B4C in Ti6Al4V increased the average compressive yield strength (YS) to 1440 MPa from 972 MPa for the control Ti6Al4V, i.e., >48% increase without any significant change in the elastic modulus. The radial multi-material structures did not exhibit any changes in the compressive modulus compared to Ti6Al4V but displayed an increase in the average compressive YS to 1422 MPa, i.e., >45% higher compared to Ti6Al4V. Microstructural characterization revealed a smooth transition from the pure Ti6Al4V at the core to the Ti64-B4C composite outer layer. No interfacial failure was observed during compressive deformation, indicating a strong metallurgical bonding during multi-material radial composite processing. Our results demonstrated that a significant improvement in mechanical properties can be achieved in one AM build operation through designing innovative multi-material structures using DED-based AM.
more » « less- Award ID(s):
- 1934230
- NSF-PAR ID:
- 10536684
- Publisher / Repository:
- ACCScience Publishing
- Date Published:
- Journal Name:
- Materials Science in Additive Manufacturing
- Volume:
- 3
- Issue:
- 3
- ISSN:
- 2810-9635
- Page Range / eLocation ID:
- 3571
- Subject(s) / Keyword(s):
- Additive manufacturing 3D Printing Ti6Al4V B4C Multi-material structures.
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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