Efficient Synthesis of Nanostructured TiC Powder by Reaction Milling

Abstract

Titanium carbide (TiC) is widely used in industrial applications due to its high melting temperature, hardness, elastic modulus, electrical and thermal conductivity, excellent refractoriness and chemical inertness. It has been widely produced for some industrial applications such as hard coating to protect the surface of cutting tool from wear and abrasion. TiC has low density, which is desirable for lightweight applications. Reaction milling is a novel technique, making it possible to synthesize ultrafine-grained TiC at room temperature. It is a process where simultaneous milling and chemical reaction takes place in a highly energetic environment. The gravity field becomes an important limiting factor in conventional ball mills, as the energy in these kinds of mills is very small. The planetary mill overcomes the limitation of the gravitational field, supplying a strong acceleration field. The dual-drive planetary mill was developed specifically for the synthesis of nanocrystalline titanium carbide has a rotating shaft that sweeps a circle of diameter 750 mm. A force field around 50 G is generated inside the mill, which is sufficient for reaction.

Nanocrystalline TiC powder is synthesized from corresponding elemental constituents by reaction milling in a specially built dual-drive planetary mill. The study shows nanocrystalline TiC powder could be produced from both Ti + graphite and Ti + activated carbon powder after 10 hours of milling. Raman spectroscopy provides evidence in support of formation of TiC after 10 hours of milling. Scanning electron microscopy (SEM) reveals the size reduction and morphology of particles at different stages of milling. Transmission electron microscopy (TEM) shows the formation of nanocrystalline TiC powder with particle size in the range of 50 to 200 nm.