Balancing strength and ductility is crucial for structural materials, yet often presents a paradoxical challenge. This research focuses on crafting a unique bimetallic structure, combining non-magnetic, stainless steel 316L (SS316L) with limited strength but enhanced ductility and magnetic, martensitic 17-4 PH with higher strength but lower ductility. Utilizing a powder-based laser-directed energy deposition (L-DED) system, two vertical bimetallic configurations (SS316L/17-4 PH) and a radial bimetallic structure (SS316L core encased in 17-4 PH) were fabricated. Monolithic SS316L, 17-4 PH, and a 50% SS316L/50% 17-4 PH mixture were printed. The printed samples' phase, microstructure, room temperature mechanical properties, and fracture morphology were examined in as-printed conditions. Bimetallic samples exhibited both phases, with a smooth grain transition at the interface. Radial bimetallic samples demonstrated higher mechanical strength than other compositions, except 17-4 PH. These findings showcase the potential of the L-DED approach for creating functional components with tailored mechanical properties.
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This content will become publicly available on August 31, 2025
Additively Manufactured 17-4 PH Stainless Steels for Fracture Management Devices
Stainless steel 316L (SS316L) is widely used in fracture management devices. However, SS316L does not offer any bacterial infection resistance and can cause metal-ion sensitivity due to Ni-ions' presence. 17-4PH can emerge as a promising substitute due to the intrinsic antibacterial properties of copper, a 75% reduction in nickel content, and superior mechanical properties. SS316L and 17-4 PH were manufactured using laser-directed energy deposition (LDED). 17-4PH specimens surpassed the compressive strength of SS316L by over 150%. A static magnetic field was generated in 17-4 PH specimens to understand in vitro bone cell-material interactions. In vitro human fetal osteoblast cell culture and bacterial inhibition study using Staphylococcus aureus and Pseudomonas aeruginosa were carried out on these specimens with SS316L as control and as-processed and magnetized 17-4 PH as treatments. Results demonstrated that magnetized 17-4 PH exhibited 25% enhancement in hFOB proliferation and 70% reduction in bacterial colonization compared to SS316L.
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- Award ID(s):
- 1934230
- NSF-PAR ID:
- 10536685
- Publisher / Repository:
- Taylor and Francis
- Date Published:
- Journal Name:
- Virtual and physical prototyping
- ISSN:
- 1745-2759
- Page Range / eLocation ID:
- 10.1080/17452759.2024.2397698
- Subject(s) / Keyword(s):
- 17-4PH Additive manufacturing 3D printing hFOB cell culture Staphylococcus aureus (S. aureus) Pseudomonas aeruginosa (P. aeruginosa).
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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