Mechanochemical Synthesis of Ni–Cr3C2 Nanocomposite

The aim of this research is to synthesize Ni–Cr₃C₂ nanocomposite powder by mechanochemical method at low temperature from initial powder oxides of NiO and Cr₂O₃. In this study, magnesium was added for the reduction of the oxide material and graphite was used for carbidification. According to the calculation of the adiabatic temperature it was found that the synthesis of the Cr₃C₂ was self propagating. The mechanochemical process was done in a high energy planetary ball mill with a ball-to-powder weight ratio of 1 : 20. XRD analysis was used for phase determination. The results showed that the Ni–Cr₃C₂ composite was gradually synthesized after 3 h milling and the synthesized products obtained during the milling process were Cr₃C₂, Ni, and MgO. Furthermore, it was seen that the addition of 10% excess Mg to the powder mixture changed the reaction from gradual stage to combustion. The morphological studies using FESEM showed that the composite powder had a semi-spherical morphology. XRD patterns and elemental map images showed that after the acid leaching process, MgO was completely removed. The study on the particle size of the composite powder by TEM showed that the size of particles was around 55 nm.