Experimental investigation of the Ce–Cu phase diagram

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, Cu 6Ce, Cu 5Ce, Cu 4Ce, Cu 2Ce, and CuCe, have been confirmed. Cu 6Ce and Cu 2Ce melt congruently at 947 °C and 810 °C, respectively. Cu 5Ce, Cu 4Ce, and CuCe are formed through peritectic reactions, L + Cu 6Ce ↔ Cu 5Ce at 799 °C, L + Cu 5Ce ↔ Cu 4Ce at 792 °C, and L + Cu 2Ce ↔ CuCe at 492 °C, respectively. Three eutectic reactions, L ↔ (Cu) + Cu 6Ce at 879 °C, L ↔ Cu 4Ce + Cu 2Ce at 753 °C, and L ↔ CuCe + (γCe) at 407 °C, have been observed. One catatectic reaction, (δCe) ↔ L + (γCe) at 702 °C, was determined. According to the present experimental results, the Ce–Cu phase diagram is revised.