A series of Fe-xCr-yMn-zAl alloys have been examined by tensile test and electron microscopy following irradiation in JMTR to 5x10^ n/m^2 at about 470 K. After the irradiation, 0.2% proof stress, ultimate tensile stress and total elongation were compared with the unirradiated data. From this experiment, it can be assumed that appropriate composition in these alloys is as follows : Fe-10Cr-(20-25)Mn-3Al for ferritic alloys, and Fe-10Cr-30Mn for austenitic alloys
