Experimental investigation of the Ce-Cu phase diagram

Highlights: → We re-investigated the Ce-Cu phase diagram by means of experimental measurements. → Seven temperatures for the invariant reactions were confirmed, while two temperatures for the invariant reactions were revised. → The updated Ce-Cu phase diagram was presented in this work. - Abstract: The binary Ce-Cu system has been re-investigated via the selected eighteen key alloys by means of the differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM) with energy dispersive X-ray analysis techniques. Five intermetallic compounds, Cu6Ce, Cu5Ce, Cu4Ce, Cu2Ce, and CuCe, have been confirmed. Cu6Ce and Cu2Ce melt congruently at 947 deg. C and 810 deg. C, respectively. Cu5Ce, Cu4Ce, and CuCe are formed through peritectic reactions, L + Cu6Ce ↔ Cu5Ce at 799 deg. C, L + Cu5Ce ↔ Cu4Ce at 792 deg. C, and L + Cu2Ce ↔ CuCe at 492 deg. C, respectively. Three eutectic reactions, L ↔ (Cu) + Cu6Ce at 879 deg. C, L ↔ Cu4Ce + Cu2Ce at 753 deg. C, and L ↔ CuCe + (γCe) at 407 deg. C, have been observed. One catatectic reaction, (δCe) ↔ L + (γCe) at 702 deg. C, was determined. According to the present experimental results, the Ce-Cu phase diagram is revised.