Compositionally graded hydroxyapatite/tricalcium phosphate coating on Ti by laser and induction plasma

Area of Science:

• Biomaterials Engineering
• Materials Science
• Surface Engineering

Background:

• Hydroxyapatite (HA) coatings enhance the biocompatibility of titanium (Ti) implants.
• Traditional coating methods face challenges in achieving optimal adhesion and structural integrity.
• Developing advanced coating techniques is crucial for improving implant performance.

Purpose of the Study:

• To fabricate compositionally graded hydroxyapatite (HA) coatings on titanium (Ti) substrates.
• To combine Laser Engineering Net Shaping (LENS) and radio frequency induction plasma spraying for advanced coating.
• To evaluate the structural, mechanical, and in vitro biocompatibility properties of the developed coatings.

Main Methods:

• Fabrication of Ti-HA composite layer using LENS.
• Deposition of HA coating via RF induction plasma spraying.
• Characterization using X-ray diffraction, hardness testing, and in vitro cell culture.

Main Results:

• Laser processing resulted in a diffused Ti-HA interface, increasing hardness to 922 ± 183 Hv.
• Plasma spraying ensured strong adhesion (21 MPa) and structural stability.
• In vitro studies demonstrated enhanced osteoblast activity with the plasma-sprayed HA coatings.

Conclusions:

• A hybrid LENS and plasma spraying approach successfully created graded HA coatings on Ti.
• The developed coatings exhibit superior hardness, adhesion, and biocompatibility compared to uncoated Ti.
• This fabrication strategy offers a promising route for next-generation orthopedic and dental implants.