The equilibrium diagrams of the Th-Fe and Th-Co systems

Abstract

The phase diagrams of the Th-Fe and Th-Co systems were investigated over almost all of the composition range using differential thermal analysis, micrographic analysis, X-ray diffraction and electron microscopy. The proposed general shape of the equilibrium diagrams is accepted but with some significant corrections concerning the characteristic temperatures and the melting behaviour of some compounds, eutectic compositions and temperatures of polymorphic transformations. All intermediate phases were confirmed and their lattice constants determined accurately. The 0–15 and 85–100 at.% Fe or Co regions of the diagrams were not investigated because of contamination of the alloys with the container material. They were drawn taking into account thermal effects obtained only on the heating run and on the basis of earlier investigations.