EXTRUSION PROCESSING OF FECO

Ingots of three FeCo alloys, Fe-70 at% Co, Fe-50 at% Co and Fe 30 at% Co, were successfully extruded at 1000-degrees-C, then re-extruded at 750-degrees-C in order to produce fine-grained material. The resulting microstructures were examined both optically and by transmission electron microscopy. It was found that increasing the Fe : Co ratio produces less complete recrystallization : Fe-70 at % Co was completely recrystallized even after both the 1000 and 750-degrees-C extrusions, whilst Fe-30 at % Co was partially recrystallized after the 1000-degrees-C extrusion. Single dislocations were present in the extruded alloys except single-extruded Fe-30 at % Co, in which dislocation pairs were observed.