The synthesis of nano-structured NbC and TaC and characterization by Rietveld's refinement method

Full text: Refractory metals carbides have great importance on the industrial sector because their high hardness, high melting or decomposition temperature, and great wear resistance, witch allow these carbides to be used on the aero space industry. These applications can be improved by using nanotechnology and powder metallurgy once there increases material surface using those techniques. The objective of this work is to produce nanostructured carbide, at a low temperature (980 deg C), through a gas-solid reaction, from a niobium-oxalate to NbC and tantalum-oxalate of ammonia to TaC in a gaseous atmosphere, in two hours reaction. These carbides were characterized by XRD, SEM, and analyzed by Ritveld's refinement Method. (author)