Isoplethic section in the quaternary system Fe-Co-Sm-Pr at 800 degrees C with Sm/Pr=1 and R <= 33.3 at% (R=Sm0.5Pr0.5)

Isoplethic section in the quaternary system Fe-Co-Sm-Pr at 800 degreesC wit h Sm/Pr=1 and R less than or equal to 33.3 at% (R=Sm0.5Pr0.5) was determine d by using optical microscopy, X-ray diffraction analysis and electron prob e microanalysis. There are five intermetallic phases: (Sm,Pr)(Fe,Co)(2), (S m,Pr)(Fe,Co)(3), (Sm,Pr)(2)(Fe,Co)(7), (Sm,Pr)(5)(Fe,Co)(19) and (Sm,Pr)(2) (Fe,Co)(17). The isoplethic section of the Fe-Co-R system consists of eight single-phase regions, eleven two-phase regions and five three phase region s. The (Sm,Pr)(2)(Fe,Co)(7) phase in R-2(Fe1-xCox)(7) alloys dissolves near ly 15 at % Fe at 800 degreesC and no (Sm,Pr)(Fe,Co)(5) phase exists. (C) 20 01 Elsevier Science B.V. All rights reserved.