[en] Phase equilibria between the fcc matrix and the hcp nitride phase were installed by long-time heat treatment at 1273 and 1073 K, respectively, in different Fe-Cr-Mn-N alloys. The composition of the phases was determined applying wavelength-dispersive X-ray microanalysis. The results are compared with thermodynamic calculations using published data describing the fcc and the hcp phases in the system Fe-Cr-Mn-N. The agreement is satisfactory at medium concentrations at 1273 K but there are considerable differences at 1073 K. (orig.)