Vol. 29 No. 2 (2026) Cover Image
Vol. 29 No. 2 (2026)

Published: June 20, 2026

Pages: 291-300

Articles

Functionally Graded Materials of Stainless Steel 316L-Inconel 625: Optimization of the study characteristics through Porosity, Microstructure, and Mechanical Performance

Samir Ali 1 Ziad Taha 1 Barbara Previtali 2
1 Institute of Laser for Postgraduate Studies, University of Baghdad, Baghdad, Iraq
2 Department of Mechanical Engineering, Politecnico di Milano, Via La Masa 1, 20156 Milan, Italy
History
  • Received: January 21, 2026
  • Revised: February 26, 2026
  • Accepted: March 17, 2026
  • Available Online: June 20, 2026
DOI

https://doi.org/10.29194/NJES.29020291

Abstract

Functionally graded materials were created using laser-directed energy deposition technology. This work examines how different mixing ratios of Stainless Steel 316L and Inconel 625 affect the relative density and porosity of these materials. Twelve samples were created using a constant laser power of 600 W, three different laser scan speeds (20, 25, and 30 mm/s), and four different SS316L/IN625 transition ratios (85%/15%, 60%/40%, 40%/60%, and 15%/85%). To determine the volumetric distribution across the compositional gradients, the porosity and relative density measurements were taken. Optical and scanning electron microscopy were used for microstructural analytical characterization to differentiate between compositional gradients in grain shape and phase distribution. The mechanical performance was examined using microhardness measures, namely the Vickers method. This study applied to prove the process parameters and compositional transformations to the resulting microstructural features and mechanical properties, providing insight into optimizing the laser-directed energy deposition-manufactured functionally graded materials for advanced performance. The best graded composition was found that gives the best overall performance based on experimental data.

Keywords

References

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