In joining Fe-alloys and Cu-containing alloys to access the high strength of steels and corrosion resistance of Cu-alloy, cracking is widely observed due to the significant Cu microsegregation during the solidification process, resulting in an interdendritic Cu-rich liquid film at the end of solidification. By fabricating functionally graded materials (FGMs) that incorporate additional elements like Ni in the transition region between these terminal alloy classes, the hot cracking can be reduced. In the present work, the joining of stainless steel 316L (SS316L) and Monel400 by modifying the Ni concentration in the gradient region was studied. A new hot cracking criterion based on hybrid Scheil-equilibrium approach was developed and validated with monolithic multi-layer samples within the SS316L-Ni-Monel400 three-alloy system and a SS316L to 55/45 wt% SS316L/Ni to Monel400 FGM sample fabricated by direct energy deposition (DED). The new hot cracking criterion, based on the hybrid Scheil-equilibrium approach, is expected to help design FGM paths between other Fe-alloys and Cu-containing alloys as well.
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Understanding the antibacterial efficacy of additively manufactured copper-added 316L stainless steel
In response to the growing demand for advanced materials with inherent infection resistance, this research investigates the properties of 316L stainless steel with copper, produced through laser-directed energy deposition additive manufacturing. The study focuses on three compositions: pure 316L, 316L with 3 wt.% Cu, and 316L with 5 wt.% Cu. Compressive strength measurements and Vickers hardness tests were conducted to assess mechanical properties, while microstructural characterization and X-ray diffraction analysis provided insights into the material’s physical properties. This research extends beyond physical and mechanical properties by exploring the on-contact antibacterial efficacy against Staphylococcus aureus and Pseudomonas aeruginosa up to 72 h. The addition of Cu reduced the ability of bacterial colonization of both strains on the metal surface. The findings of this investigation have the potential to benefit the biomedical devices, contributing to both structural and biofunctional properties of materials.
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- Award ID(s):
- 1934230
- PAR ID:
- 10650632
- Publisher / Repository:
- AccScience Publishing
- Date Published:
- Journal Name:
- Materials Science in Additive Manufacturing
- Volume:
- 4
- Issue:
- 1
- ISSN:
- 2810-9635
- Page Range / eLocation ID:
- 7357
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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