Ti6Al4V-Bioglass-Copper Composites for Load-Bearing Implants

Area of Science:

• Biomaterials Science
• Materials Engineering
• Orthopedic Surgery

Background:

• Cobalt-chromium alloys in hip and knee replacements raise concerns about cobalt ion release.
• Ceramic alternatives face challenges with long-term mechanical stability.
• Ti6Al4V (Ti64) shows promise but lacks sufficient wear resistance for articulating surfaces.

Purpose of the Study:

• To develop a novel Ti64-based composite with enhanced wear resistance, biocompatibility, and antibacterial properties for orthopedic implants.
• To investigate the effects of incorporating 45S5 bioglass (BG) and copper (Cu) into Ti64.
• To evaluate the material's performance using various characterization and testing methods.

Main Methods:

• Laser-directed energy deposition (L-DED) additive manufacturing was used to create Ti64, Ti64-1 wt% BG, Ti64-3 wt% BG, and Ti64-3 wt% BG-3 wt% Cu composites.
• Microstructural characterization and phase analysis were performed.
• Uniaxial compression, biotribological, in vitro biocompatibility (osteoblast cells), and antibacterial (Staphylococcus aureus) tests were conducted.

Main Results:

• BG addition localized at melt pool boundaries, while Cu distributed uniformly.
• Incorporation of BG and Cu increased the composite's strength.
• Wear resistance significantly improved due to BG and Cu, with a protective nanoscale tribofilm forming on BG-containing samples.
• Enhanced biocompatibility with human osteoblast cells and inherent antibacterial properties from copper were observed.

Conclusions:

• The novel Ti64-BG-Cu composite demonstrates superior performance compared to traditional materials.
• This advanced biomaterial offers enhanced biocompatibility, antibacterial characteristics, and wear resistance.
• The findings suggest a promising new material for total hip and knee arthroplasty applications, potentially reducing revision rates and improving patient outcomes.