Redetermination of the Eutectic Composition of the Ni-P Binary Alloy

Abstract

A series of Ni-P alloys (Ni-rich) have been synthesized and solidified. It is found that the solidification microstructure of the Ni-19.0 at.%P alloy that has long been regarded as the eutectic composition contains many primary phase dendrites besides rod eutectics. In contrast, only rod eutectic microstructure appears in the samples of Ni-19.6 at.%P, and this alloy shows the lowest end temperature of melting among all the compositions investigated. The results indicate that the actual eutectic composition at the Ni-rich part of the Ni-P system is Ni-19.6 at.%P. The eutectic temperature is determined to be about 1163 K by the differential scanning calorimetry analysis.

Remelting-induced anomalous eutectic formation during solidification of deeply undercooled eutectic alloy melts

“…With a volume fraction as low as 0.22, a-Ni exists in a fibrous form in the near-equilibrium eutectic structure [37]. As the undercooling prior to nucleation increases up to 25 K, anomalous eutectics begin to appear in the solidification microstructure.…”

Crystal growth by Bridgman and Czochralski method of the ferromagnetic quantum critical material YbNi 4 P 2

“…The binary Ni-P phase diagram shows a low-melting eutectic, Ni 81 P 19 [30]. A detailed investigation identified Ni 80.4 P 19.6 as the eutectic composition with the eutectic temperature T E = 875 • C [31]. We have used this eutectic as a self-flux in one series of experiments utilizing a Bridgman and in an other series the Czochralski technique to grow YbNi 4 P 2 single crystals.…”