Characterization of sintered titanium/hydroxyapatite biocomposite using FTIR spectroscopy

Area of Science:

• Biomaterials Science
• Materials Chemistry
• Ceramics Engineering

Background:

• Hydroxyapatite (HA) is a key biomaterial for bone regeneration.
• Understanding HA phase stability during composite processing is crucial for implant performance.
• Titanium (Ti) is often used in HA-based biocomposites.

Purpose of the Study:

• To investigate the phase transformation of HA in a Ti/HA biocomposite during sintering.
• To determine the influence of sintering temperature and Ti presence on HA decomposition.
• To identify the decomposition products of HA under various thermal conditions.

Main Methods:

• Fourier Transform Infrared (FTIR) spectroscopy was utilized for phase analysis.
• Sintering experiments were conducted on pure HA and Ti/HA biocomposites.
• Varying sintering temperatures were applied in an argon atmosphere.

Main Results:

• Pure HA remained stable up to 1200°C, though dehydroxylation increased with temperature.
• In Ti/HA, Ti presence significantly promoted HA dehydroxylation and decomposition starting at 800°C.
• Decomposition products included tetracalcium phosphate (TTCP) and calcium oxide (CaO); tricalcium phosphate (TCP) was absent.
• At high temperatures (>1200°C) in Ti/HA, HA decomposed into CaO and amorphous phases.

Conclusions:

• Titanium acts as a catalyst for hydroxyapatite decomposition during sintering.
• The presence of titanium alters the thermal stability and decomposition pathway of HA in biocomposites.
• Careful control of sintering parameters is necessary for Ti/HA biocomposites to manage HA phase stability.