Improving Pure Titanium's Biological and Mechanical Characteristics through ECAP and Micro-Arc Oxidation Processes.

Area of Science:

• Materials Science
• Biomedical Engineering
• Surface Engineering

Background:

• Commercially pure titanium (CP Ti) has limitations in biomedical applications due to insufficient mechanical strength.
• Enhancing CP Ti properties is essential for improving the feasibility of medical implants.
• Severe plastic deformation (SPD) techniques like equal-channel angular pressing (ECAP) can refine grain structure.

Purpose of the Study:

• To surface modify CP Ti using micro-arc oxidation (MAO) or plasma electrolytic oxidation (PEO) with calcium and phosphorus-containing mineral solutions.
• To evaluate the impact of these modifications on the mechanical, corrosion, and biological properties of CP Ti.
• To assess the potential of ECAP and surface modification for advanced biomedical applications.

Main Methods:

• Surface modification of CP Ti via MAO/PEO with Ca and P solutions.
• Characterization using X-ray diffraction (XRD), optical microscopy (OM), and scanning electron microscopy (SEM).
• Mechanical testing (microhardness), corrosion resistance evaluation (potentiodynamic measurements, electrochemical impedance spectroscopy), and in vitro cytotoxicity assays (ELISA).

Main Results:

• Surface modification significantly improved mechanical strength and corrosion resistance, with the 2-pass MAO showing the lowest corrosion rate (0.495 mmpy).
• Electrode potentials for coated samples (1.44 V and 1.47 V) indicated high effectiveness in reducing corrosion.
• In vitro studies demonstrated acceptable behavior of dental pulp and periodontal cells on modified surfaces, with cytotoxicity assessed according to ISO 10993-5 guidelines.

Conclusions:

• Mechanical grain refinement via ECAP combined with surface modification enhances the mechanical and biomechanical properties of CP Ti.
• Surface-treated CP Ti exhibits superior corrosion resistance, essential for long-term implant performance.
• The study provides valuable insights into the biocompatibility and potential of modified CP Ti for dental and orthopedic applications.