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In this study, hematite (Fe₂O₃) and aluminum (Al) powder mixtures were mechanically alloyed in a high-energy shaker ball mill to synthesize the iron-alumina (Fe-Al₂O₃) nanocomposite powder. The structural changes and phase developments occurring during mechanochemical process were studied by X-ray diffractometery (XRD) and scanning electron microscopy (SEM). The results showed that mechanochemical reaction of Fe₂O₃ and Al completed after 3 hours of milling time in a nanocrystalline Fe and Al₂O₃ embedded form and further milling produced a Fe-Al₂O₃ nanocomposite powder. Kinetics consideration according to the calculated adiabatic temperature demonstrated the sudden displacement reaction during mechanical alloying that accord well with XRD results. Also, particle size decrease as well as crystallite size with increasing the milling time.

The ZnO nanoparticles were synthesized by using a combination of precipitation and mechanical milling. Basic zinc carbonate precursor was prepared by precipitation process using zinc sulfate as the starting material. Under the mechanochemical effect, parts of the basic zinc carbonate were transformed into ZnO. In the closed system of milling, in order to produce pure ZnO nanoparticle phase, further heat processing was needed. But the ultimate ZnO particles were more uniform and the particle size distribution was narrower. The effects of mechanical milling process on properties of ultimate ZnO particles were also investigated.

Synthetic hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂, HA) is an important material used for orthopaedic and dental implant applications. The biological hydroxyapatite in the human bone and tooth is of nano size and differs in composition from the stiochiometric HA by the presence of other ions such as carbonate, magnesium and fluoride, etc. Osseointegration is enhanced by using nanocrystalline HA. This stimulates the interest in synthesizing nanocrystalline HA by different routes and among the methods, mechanochemical seems to form fine grain size and uniform characteristic nanocrystalline materials. Fluorinated hydroxyapatite (FHA, Ca₁₀(PO₄)₆(OH)_2-xF_x) possesses higher corrosion resistance in biofluids than pure HA and reduces the risk of dental caries. The present work deals with the synthesis of nanocrystalline FHAs by mechanochemical processing. The nanomaterials were characterized using X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) methods. Nano FHA of about 27-46 nm size was observed. The functional groups present in the FHA powders were ascertained by Fourier transform infrared spectroscopy (FT-IR) and Laser Raman spectroscopy. A gradual decrease in intensity of the OH^- band at 655 and 3572 cm^-1 has been observed with increasing fluorine substitution. The TEM micrograph shows that the powder is highly agglomerated and particle size is below 50 nm.

The ZnO nanoparticles were synthesized by using a combination of precipitation and mechanical milling. Basic zinc carbonate precursor was prepared by precipitation process using zinc sulfate as the starting material. Under the mechanochemical effect, parts of the basic zinc carbonate were transformed into ZnO. In the closed system of milling, in order to produce pure ZnO nanoparticle phase, further heat processing was needed. But the ultimate ZnO particles were more uniform and the particle size distribution was narrower. The effects of mechanical milling process on properties of ultimate ZnO particles were also investigated.

Mechanochemistry provides a new method for surface modification of nanoparticles. It not only can prepare ultrafine powder, but also achieve its surface modification. Mechanochemical surface modification is a modification method of utilizing mechanochemical reaction during the ball milling, which modification effect is better than that of traditional modification method. The paper reviews the progress in the research of surface modification of nanoparticles by mechanochemical method, discusses the mechanism of modification and the research status of wet and dry mechanochemical surface modification. Some technological parameters of mechanochemical surface modification are emphatically considered. And the application of mechanochemical surface modification is introduced. Finally, some insights of coming research target and applications prospect of mechanochemical surface modification are anticipated.