Mechanochemical synthesis of single phase nanocrystalline forsterite powder

Pure nanocrystalline forsterite (Mg₂SiO₄) powder was successfully synthesized by mechanochemical route and subsequent annealing. The starting materials were talc (Mg₃Si₄ O₁₀(OH) ₂) and magnesium carbonate (MgCO₃) powders. To produce forsterite powder, first talc and magnesium carbonate powders were calcined at 1200°C for 1 h and 700°C for 2 h, respectively. After that the mixture of obtained powders was milled by a planetary ball mill, and then annealed at 1000°C and 1200°C for 1 h. Thermogravimetric (TG) analysis, X-ray diffraction (XRD), and scanning electron microscopy (SEM) techniques were utilized to characterize the initial and prepared powders. The results showed that a single phase nanocrystalline forsterite powder with a crystallite size of 49 nm was obtained after 40 h milling and subsequent annealing at 1000°C for 1 h.