Ti-SrO metal matrix composites for bone implant materials

Area of Science:

• Materials Science
• Biomaterials Engineering
• Composite Materials

Background:

• Titanium (Ti) and its alloys are widely used in biomedical implants due to their excellent biocompatibility and mechanical properties.
• Enhancing the mechanical properties and biocompatibility of titanium-based materials is crucial for improving implant performance and longevity.
• Metal matrix composites (MMCs) offer a promising route to tailor material properties for specific applications.

Purpose of the Study:

• To fabricate and characterize titanium-strontium oxide (Ti-SrO) metal matrix composites (MMCs) using the powder metallurgy method.
• To investigate the effect of varying strontium oxide (SrO) weight ratios on the mechanical properties of Ti-SrO MMCs.
• To evaluate the in vitro biocompatibility of the fabricated Ti-SrO MMCs for potential biomedical applications.

Main Methods:

• Fabrication of Ti-SrO MMCs with 0, 1, 3, and 5% SrO by weight using powder metallurgy.
• Mechanical testing including compressive strength, ultimate strain, elastic moduli, and micro hardness measurements.
• In vitro biocompatibility assessment using MTS assay for cell proliferation and alkaline phosphatase activity, along with cell morphology analysis via confocal and scanning electron microscopy.

Main Results:

• Compressive strength increased from 982 MPa to 1753 MPa with increasing SrO content from 0 to 5%.
• Ultimate strain decreased from 0.28 to 0.05, while elastic moduli and micro hardness were significantly enhanced with SrO addition.
• Ti-3%SrO MMCs exhibited optimal in vitro biocompatibility, showing enhanced osteoblast-like cell proliferation without significant negative impact on alkaline phosphatase activity.

Conclusions:

• The addition of SrO to titanium effectively enhances the mechanical properties of Ti-SrO MMCs, attributed to the Hall-Petch effect and dispersion strengthening.
• Ti-SrO MMCs, particularly Ti-3%SrO, demonstrate promising in vitro biocompatibility, suggesting their potential for use in bone tissue engineering and orthopedic implants.