Journal of Advanced Materials and Technologies

Journal of Advanced Materials and Technologies

Effect of Silicon Addition on the Microstructure and Hardness of Ti-6Al-4V Alloy Fabricated by Selective Laser Melting

Document Type : Original Reaearch Article

Authors
Amir Hossein Gholami 1
Sayed Farshid Kashani-Bozorg 2
Mohammad Reza Barati 3
1 MSc Student, School of Metallurgy and Materials Engineering, University of Tehran, Tehran, Iran.
2 Professor, School of Metallurgy and Materials Engineering, University of Tehran, Tehran, Iran.
3 Assistant Professor, Department of Advanced Materials and New Technologies, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran.
10.30501/jamt.2026.541757.1336
Abstract
The application of additive manufacturing technologies for titanium alloys is expanding in both research and industrial sectors. In this study, selective laser melting was employed to fabricate and investigate the effects of adding 1 wt.% silicon to the Ti-6Al-4V alloy. The microstructure of the fabricated selective laser melting samples consisted of fish-type melted regions normal to the build direction. Columnar β-Ti grains grew in the opposite direction of heat flow, namely along the build direction. The results indicated that the addition of 1 wt.% silicon led to grain refinement and a reduction in the width of the primary columnar β-Ti grains from approximately 70 to approximately 40 µm. This grain refinement, resulting from the presence of silicon, also contributed to an increase in the average microhardness of the alloy, such that the microhardness value increased from approximately 417 to approximately 481 HV in the build direction plane.
Keywords
Selective Laser Melting
Ti6Al4V Alloy
Silicon
Microstructure
Microhardness
Subjects
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  • Receive Date 21 August 2025
  • Revise Date 24 November 2025
  • Accept Date 22 December 2025