Differential Scanning Calorimetry Studies on Ni-Ni₃B Alloys

Abstract:

Solidification behaviors of hypoeutectic Ni-3.3wt% B and hypereutectic Ni-4.5wt% B alloys were investigated by using differential scanning calorimetry (DSC) technology. Experimental results showed that the solidification behaviors are similar for the two kinds of alloys with small sizes, i.e. three transformed peaks (corresponding to L→α-Ni, L→Ni-Ni₂₃B₆ and Ni₂₃B₆→Ni+Ni₃B, respectively) appear in the cooling curves, and three phases (primary phase α-Ni, rod eutectic and dot precipitates) appear in the microstructures, which are different from that of the alloys with large sizes. It can be attributed to the fact that the nucleation of α-Ni and Ni₂₃B₆ phases are easier than that of Ni₃B phase for small samples of hypoeutectic and hypereutectic Ni-Ni₃B alloys.

• Periodical: Materials Science Forum (Volume 817)
• Pages: 556-559
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.817.556
• Online since: April 2015
• Authors: Jun Feng Xu*, Feng Liu, Man Zhu, Zeng Yun Jian
• Keywords: Eutectic, Solidification, Undercooling

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