In situ NbC and VC nanoparticles reinforced Fe-Si-Mn-Nb-V matrix composite was carried out using a plasma jet with a plasma gas flow of (Ar + CH4) for very short time. The process involve improving the efficiency of the reaction in terms of consumption of the available active nitrogen atoms as well as the production of very fine and homogeneous distribution of all reinforcing phases of ceramic particles, preferable in the nanometer range. The nanoreinforcements synthesized by in situ reaction in this hybrid composite are NbC and VC ceramic particles.