In our previous work (IEEE Trans. Mag. vol.36, p.3315, (2000)), we studied the effect of carbon on the formation and magnetic properties of nanocomposite Nd2Fe14(C,B)/α-Fe magnets. In the Nd10Fe82B8-xCx (x=0,2,4,5, 6,7) as-spun ribbons for x=0-4 have a majority 2:14:1 phase with some α-Fe, whereas, for larger x the mixture of 2:14:1 phase and α-Fe is obtained only at certain wheel speeds range. Beyond this range, the 2:17 phase and a significant amount of α-Fe were obtained instead, which transform into the tetragonal 2:14:1 phase after annealing. Magnetic measurements showed a slight enhancement of the coercivity (8.7 kOe) for x=2 and then a decrease for larger x. The drop of the coercivity with carbon content can be related to the change in the crystallization behavior and the coarsening of the microstructure. In this work, we study the effect of small substitutions (i.e. Zr, Nb, Cr, Ga, etc.) for iron, in melt-spun Nd10Fe82-xMxB2C6 in order to optimize their microstructure and therefore their magnetic hysteresis properties.