The Ni-Re-Zr (Nickel-Rhenium-Zirconium) System

Abstract

The Ni-Re system [Massalski2] (Fig. 1) is a simple peritectic system. The peritectic reaction e + LM c occurs at 1670 C where e and c are the terminal solid solutions (Re) and (Ni), respectively. The Ni-Zr system [1991Nas] (Fig. 2) shows the presence of eight intermediate phases: Ni5Zr(e), Ni7Zr2(p), Ni3Zr(j), Ni21Zr8(h), Ni10Zr7(b), Ni11Zr9(m), NiZr(/), and NiZr2(n), of which the p, /, and n phases melt congruently at 1440, 1260, and 1120 C, respectively. All the other phases form through peritectic or peritectoid reactions: L + pM e at 1300 C, L + p M h at 1180 C, L + m M b at 1160 C, L + /M m at 1170 C, and p + h M j at 920 C. Two eutectoid reactions m +/ + b and (bZr) M (aZr) + n occur at 978 and 843 C, respectively. The p, h, m, /, and n phases are of invariant compositions. The Re-Zr system [Massalski2] (Fig. 3) has three intermediate phases. Re24Zr5(v), Re2Zr(k1) and ReZr2(f), of which the k1 phase melts congruently at 2750 C. The v phase and the f form through peritectic reactions L + k1M v at 2500 C and L + k1M f at 1640 C. Two eutectic reactions LM (Re) + v and L M f + bZr occur at 2400 and 1593 C, respectively. A eutectoid reaction bZr M f + aZr occurs between 550 and 600 C. The f phase is of invariant composition.