The formation of bulk β-Al3Ni phase in eutectic Al-5.69wt%Ni alloy solidified under high pressure

• Published in: Journal of alloys and compounds 2018-04, Vol.742, p.670-675
• Main Authors: Wang, X.H., Ran, Z., Wei, Z.J., Zou, C.M., Wang, H.W., Gouchi, J., Uwatoko, Y.
• Format: Article
• Language: English
• Subjects: Eutectic Al-5.69wt%Ni alloy; High pressure solidification; Interfacial solidification velocity; Undercooling; β-Al3Ni phase
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2018.01.272

The microstructure and formation thermodynamic of bulk β-Al3Ni phase in eutectic Al-5.69wt%Ni alloy synthesized under different pressures were systematically investigated. The results demonstrate that α, bulk β-Al3Ni, and eutectic phase exist simultaneously after solidified under 1 GPa and 2 GPa. A mathematical model was proposed to describe the interfacial solidification velocity of dilute solution alloy under high pressure, with combination of the growth model of BCT and TMK, it reveals that the β-Al3Ni phase takes precedence over the eutectic phase nucleation when the solidification pressure is greater than 0.66 GPa. •The α, bulk β-Al3Ni, and (α + β) eutectic phase coexist for eutectic Al-5.69wt%Ni alloy solidified under 1 and 2 GPa.•The eutectic point of Al-5.69wt%Ni alloy moves to 22.54% and 26.49% at 1 GPa and 2 GPa, respectively.•The interfacial solidification velocity of dilute solute decreases dramatically under high pressure.•The bulk β-Al3Ni is the fast-growing phase when the pressure is greater than 0.66 GPa.