Abstract Structure, phase transformation and magnetic properties of mechanically alloyed (MA) samples of Nd 14Fe 76M 3C 7 (M=Si, Al, Cu, Co, Ti, Nb, Ga) have been studied systematically. Compared with the original samples, the various transitional metal substitutions decrease the thermal stability of the 2-14-1 tetragonal hard magnetic phase. Substitution of Cu, Nb, Ga and Ti harms the formation of hard magnetic phases while substitution of Si, Al and Co substitution does not. Cobalt substitution decreases both the coercivity and the remanence of Nd 2(Fe,Co) 14C-based alloys. Si substituted Nd–Fe–C has the best magnetic properties in this series, with M r=6.16 kG, i H c=5.65 kOe and ( BH) max=6.8 MGOe. Al substitution increases the coercivity slightly.