Laser-Driven Surface Alloying of Ti6Al4V: Coupled Microstructural Evolution, Phase Behavior, and Mechanical...

Area of Science:

• Materials Science
• Biomedical Engineering
• Surface Engineering

Background:

• Titanium alloys like Ti6Al4V are crucial for biomedical implants due to their biocompatibility and mechanical properties.
• Enhancing the surface performance of Ti6Al4V is essential for improving implant longevity and functionality.
• Antimicrobial surface properties are highly desirable to prevent implant-associated infections.

Purpose of the Study:

• To investigate the microstructural and mechanical changes in Ti6Al4V surfaces after laser surface alloying (LSA) with silver (Ag) and copper (Cu).
• To evaluate the potential of LSA with Ag and Cu for developing enhanced biomedical implant surfaces.
• To compare the effects of Ag and Cu alloying on the hardness and microstructure of Ti6Al4V.

Main Methods:

• Laser Surface Alloying (LSA) using a 1000 W pulsed laser to introduce Ag and Cu into Ti6Al4V surfaces.
• Microstructural characterization using Electron Backscatter Diffraction (EBSD) and Energy Dispersive Spectroscopy (EDS).
• Phase identification via X-ray Diffraction (XRD) and hardness testing.

Main Results:

• LSA with Ag resulted in ultrafine martensitic structures and moderate hardness increase.
• LSA with Cu promoted Ti2Cu intermetallic phases and significant hardness enhancement.
• Cu-alloyed zones exhibited higher hardness than Ag-alloyed zones, indicating a stronger strengthening effect.

Conclusions:

• Both Ag and Cu alloying via LSA effectively modify Ti6Al4V microstructure and improve surface hardness.
• Cu alloying offers a more pronounced surface strengthening effect compared to Ag for Ti6Al4V under the studied conditions.
• LSA-modified Ti6Al4V surfaces show potential for durable and antimicrobial biomedical applications.