Mechanic of Advanced and Smart Materials
Quarterly

Design and Characterization of SLM-Fabricated Graded Gyroid Ti-6Al-4V Porous Filters for Respiratory Applications

Document Type : Original Article

Authors

amir mohammad babaei 1
mahdi safari 2
mohammad reza karafi 3

1 Department of Mechanical Engineering, Faculty of Mechanical Engineering, Arak University of Technology, Arak, Iran.

2 Associate Professor, Department of Mechanical Engineering, Arak University of Technology, Arak, Iran

3 Associate Professor, Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran

https://doi.org/10.66224/masm.5.3.383
Abstract
Airborne particulate matter, such as fine dust and aerosols, poses serious threats to respiratory health. Conventional polymer filters suffer from limited reusability and sterilization challenges. This study presents the design, fabrication via Selective Laser Melting (SLM), and characterization of a cylindrical porous filter made from Ti-6Al-4V alloy with a graded conformal Gyroid topology. The structure features graded channel spacings (inner wall: 206 µm, mid-region: 396 µm, outer wall: 463 µm; weighted mean: 415 µm) and an effective open porosity of ~65%. The design was optimized in nTopology software to enhance cell overlap and particle trapping while maintaining airflow permeability. The sample (OD=15 mm, ID=9 mm, H=10 mm) was fabricated from Ti-6Al-4V powder (15–45 µm) and characterized after stress-relief annealing at 600°C. Results include optical metallography (acicular α phase in β matrix), metallographic measurements (mean layer spacing of 415 µm), Vickers microhardness (mean 327 HV), bulk density (4.18 g/cm³), and bulk porosity (~5.5%).

Keywords

Respiratory Filter
Additive Manufacturing
Gyroid Topology
Density
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Mechanic of Advanced and Smart Materials
Volume 5, Issue 3
Autumn 2025
Pages 383-402

  • Receive Date 23 September 2025
  • Revise Date 22 October 2025
  • Accept Date 24 October 2025

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