Ceramics-Silikáty 57 (2) 87-91 (2013)

NANO AND MICROSTRUCTURE EFFECTS ON THE BIOACTIVITY OF FORSTERITE POWDERS

Gorea M., Naghiu M-A., Tomoaia-Cotisel M., Borodi G.

Forsterite (Mg₂SiO₄) powder has been synthesized from talc (Mg₃Si₄O₁₀(OH)₂) and magnesium carbonate (MgCO₃) by applying solid state reactions method. The raw materials mixture has been milled for 10 hours until nano powders have been obtained. This mixture was then thermally treated at various temperatures. The synthesized material was structurally characterized by X-ray diffraction. Forsterite represented the main crystalline phase in the samples fired to 1100 and 1200°C, while at 1000°C small amounts of enstatite and periclase were still identified. The particles size and morphology were investigated by TEM, SEM and AFM, and the grain size distribution with a Counter Coulter-type laser granulometer. A ratio of 75 % of the particles in the samples fired to 1000, and respectively 1100°C were less than 25 nm, while the maximum size was 42 nm. For the samples fired at 1200°C, most of the particles (74 %) were larger, about 6.8 μm, with a maximum of 70 μm. In order to evaluate its bioactivity, we have immersed the forsterite powder into simulating body fluids (SBF). Following 28 days of experiment, the FTIR spectra collected on the forsterite nanopowder contained the specific hydroxylapatite bands, while in the case of the micro powder these bands are hardly visible.

Keywords: Forsterite, Nano and micro powders, Bioactivity