The phase diagram of the Ce-Pt system

The Ce-Pt phase diagram has been investigated over the whole composition range by means of differential thermal analysis (DTA), X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and micro-hardness measurements. Our main results concern the discovery of three new intermediate phases, Ce5Pt3, Ce5Pt4 and CePtx with x ≈ 4.5, and the establishment of the high temperature solid-liquid equilibria. The existence of the six intermediate phases, Ce7Pt3, Ce3Pt2, CePt, Ce3Pt4, CePt2+x and CePt5, is confirmed. The published crystal structure of CePt is found incompatible with our X-ray diffraction patterns and the room temperature microstructure of CePt suggests the presence of a low temperature solid-state transformation.