The magnetic properties and microstructures of rapidly quenched Sm-Fe-N powders with low Sm contents and Zr and Co addition have been studied. High remanence values of 9.3 kG with high H-cJ values of 7-10 kOe were obtained for isotropic powders. The x-ray diffraction analysis and transmission electron microscopy (TEM) observation showed these alloy powders to consist of a nanoscale mixture with a SmFe7Nx phase with the TbCu7-type structure and alpha-Fe in the size range of 20-30 nm. Tt is presumed that the high remanence is due to the small crystal size and exchange coupling at interphase boundaries. (C) 1995 American Institute of Physics.